131329781172 has 18 divisors (see below), whose sum is σ = 331972502498. Its totient is φ = 43776593712.

The previous prime is 131329781171. The next prime is 131329781249. The reversal of 131329781172 is 271187923131.

131329781172 is a `hidden beast` number, since 1 + 313 + 2 + 97 + 81 + 172 = 666.

It can be written as a sum of positive squares in only one way, i.e., 109669594896 + 21660186276 = 331164^2 + 147174^2 .

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

It is a super-2 number, since 2×131329781172² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131329781171) 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 5 ways as a sum of consecutive naturals, for example, 1824024703 + ... + 1824024774.

Almost surely, 2^131329781172 is an apocalyptic number.

131329781172 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

131329781172 is an abundant number, since it is smaller than the sum of its proper divisors (200642721326).

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

131329781172 is a wasteful number, since it uses less digits than its factorization.

131329781172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3648049487 (or 3648049482 counting only the distinct ones).

The product of its digits is 127008, while the sum is 45.

The spelling of 131329781172 in words is "one hundred thirty-one billion, three hundred twenty-nine million, seven hundred eighty-one thousand, one hundred seventy-two".