131121213012 has 18 divisors (see below), whose sum is σ = 331445288538. Its totient is φ = 43707070992.

The previous prime is 131121213007. The next prime is 131121213023. The reversal of 131121213012 is 210312121131.

131121213012 is a `hidden beast` number, since 1 + 311 + 212 + 130 + 12 = 666.

It can be written as a sum of positive squares in only one way, i.e., 118801544976 + 12319668036 = 344676^2 + 110994^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a super-2 number, since 2×131121213012² (a number of 23 digits) contains 22 as substring.

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

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, 1821127923 + ... + 1821127994.

It is an arithmetic number, because the mean of its divisors is an integer number (18413627141).

Almost surely, 2^131121213012 is an apocalyptic number.

131121213012 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

131121213012 is an abundant number, since it is smaller than the sum of its proper divisors (200324075526).

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

131121213012 is a wasteful number, since it uses less digits than its factorization.

131121213012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3642255927 (or 3642255922 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

Adding to 131121213012 its reverse (210312121131), we get a palindrome (341433334143).

The spelling of 131121213012 in words is "one hundred thirty-one billion, one hundred twenty-one million, two hundred thirteen thousand, twelve".