131261238531 has 16 divisors (see below), whose sum is σ = 200734033920. Its totient is φ = 84684669480.

The previous prime is 131261238481. The next prime is 131261238539. The reversal of 131261238531 is 135832162131.

131261238531 is a `hidden beast` number, since 1 + 3 + 1 + 2 + 612 + 3 + 8 + 5 + 31 = 666.

It is not a de Polignac number, because 131261238531 - 2¹⁵ = 131261205763 is a prime.

It is a super-2 number, since 2×131261238531² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (131261238539) 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, 78410895 + ... + 78412568.

It is an arithmetic number, because the mean of its divisors is an integer number (12545877120).

Almost surely, 2^131261238531 is an apocalyptic number.

131261238531 is a deficient number, since it is larger than the sum of its proper divisors (69472795389).

131261238531 is a wasteful number, since it uses less digits than its factorization.

131261238531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156823503 (or 156823497 counting only the distinct ones).

The product of its digits is 25920, while the sum is 36.

The spelling of 131261238531 in words is "one hundred thirty-one billion, two hundred sixty-one million, two hundred thirty-eight thousand, five hundred thirty-one".