131221231100 has 18 divisors (see below), whose sum is σ = 284750071704. Its totient is φ = 52488492400.

The previous prime is 131221231049. The next prime is 131221231123. The reversal of 131221231100 is 1132122131.

It is a super-2 number, since 2×131221231100² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 656106056 + ... + 656106255.

It is an arithmetic number, because the mean of its divisors is an integer number (15819448428).

Almost surely, 2^131221231100 is an apocalyptic number.

131221231100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

131221231100 is an abundant number, since it is smaller than the sum of its proper divisors (153528840604).

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

131221231100 is a wasteful number, since it uses less digits than its factorization.

131221231100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1312212325 (or 1312212318 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 131221231100 its reverse (1132122131), we get a palindrome (132353353231).

The spelling of 131221231100 in words is "one hundred thirty-one billion, two hundred twenty-one million, two hundred thirty-one thousand, one hundred".