131720277681 has 16 divisors (see below), whose sum is σ = 195154248000. Its totient is φ = 87807625344.

The previous prime is 131720277677. The next prime is 131720277719. The reversal of 131720277681 is 186772027131.

131720277681 is a `hidden beast` number, since 1 + 317 + 2 + 0 + 277 + 68 + 1 = 666.

It is not a de Polignac number, because 131720277681 - 2² = 131720277677 is a prime.

It is a super-2 number, since 2×131720277681² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (131720277181) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 266650 + ... + 578396.

It is an arithmetic number, because the mean of its divisors is an integer number (12197140500).

Almost surely, 2^131720277681 is an apocalyptic number.

It is an amenable number.

131720277681 is a deficient number, since it is larger than the sum of its proper divisors (63433970319).

131720277681 is a wasteful number, since it uses less digits than its factorization.

131720277681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 327405 (or 327399 counting only the distinct ones).

The product of its (nonzero) digits is 197568, while the sum is 45.

The spelling of 131720277681 in words is "one hundred thirty-one billion, seven hundred twenty million, two hundred seventy-seven thousand, six hundred eighty-one".