131212321020 has 144 divisors (see below), whose sum is σ = 434423808000. Its totient is φ = 31792176000.

The previous prime is 131212321013. The next prime is 131212321021. The reversal of 131212321020 is 20123212131.

131212321020 is a `hidden beast` number, since 1 + 312 + 12 + 321 + 0 + 20 = 666.

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 = 131212320984 and 131212321002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131212321021) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3941445 + ... + 3974595.

It is an arithmetic number, because the mean of its divisors is an integer number (3016832000).

Almost surely, 2^131212321020 is an apocalyptic number.

131212321020 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 131212321020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (217211904000).

131212321020 is an abundant number, since it is smaller than the sum of its proper divisors (303211486980).

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

131212321020 is a wasteful number, since it uses less digits than its factorization.

131212321020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35176 (or 35171 counting only the distinct ones).

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

Adding to 131212321020 its reverse (20123212131), we get a palindrome (151335533151).

The spelling of 131212321020 in words is "one hundred thirty-one billion, two hundred twelve million, three hundred twenty-one thousand, twenty".