123311212020 has 144 divisors (see below), whose sum is σ = 384433467600. Its totient is φ = 31970930688.

The previous prime is 123311211977. The next prime is 123311212027. The reversal of 123311212020 is 20212113321.

123311212020 is a `hidden beast` number, since 12 + 331 + 121 + 202 + 0 = 666.

123311212020 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 8 ways, for example, as 11537337744 + 111773874276 = 107412^2 + 334326^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 123311211984 and 123311212002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123311212027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 10310364 + ... + 10322316.

Almost surely, 2^123311212020 is an apocalyptic number.

123311212020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 123311212020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (192216733800).

123311212020 is an abundant number, since it is smaller than the sum of its proper divisors (261122255580).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

123311212020 is a wasteful number, since it uses less digits than its factorization.

123311212020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13554 (or 13549 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 123311212020 its reverse (20212113321), we get a palindrome (143523325341).

The spelling of 123311212020 in words is "one hundred twenty-three billion, three hundred eleven million, two hundred twelve thousand, twenty".