20123212320 has 240 divisors, whose sum is σ = 71141799960. Its totient is φ = 5356855296.

The previous prime is 20123212289. The next prime is 20123212327. The reversal of 20123212320 is 2321232102.

20123212320 is a `hidden beast` number, since 20 + 1 + 2 + 321 + 2 + 320 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 11042647056 + 9080565264 = 105084^2 + 95292^2 .

It is a tau number, because it is divible by the number of its divisors (240).

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 = 20123212293 and 20123212302.

It is not an unprimeable number, because it can be changed into a prime (20123212327) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 10742904 + ... + 10744776.

Almost surely, 2^20123212320 is an apocalyptic number.

20123212320 is a gapful number since it is divisible by the number (20) 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 20123212320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35570899980).

20123212320 is an abundant number, since it is smaller than the sum of its proper divisors (51018587640).

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

20123212320 is a wasteful number, since it uses less digits than its factorization.

20123212320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2729 (or 2712 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

Adding to 20123212320 its reverse (2321232102), we get a palindrome (22444444422).

The spelling of 20123212320 in words is "twenty billion, one hundred twenty-three million, two hundred twelve thousand, three hundred twenty".