131205987 has 40 divisors (see below), whose sum is σ = 215761392. Its totient is φ = 79453440.

The previous prime is 131205979. The next prime is 131205989. The reversal of 131205987 is 789502131.

It is not a de Polignac number, because 131205987 - 2³ = 131205979 is a prime.

It is a super-2 number, since 2×131205987² = 34430022049288338, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (131205989) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 107203 + ... + 108419.

Almost surely, 2^131205987 is an apocalyptic number.

131205987 is a deficient number, since it is larger than the sum of its proper divisors (84555405).

131205987 is an equidigital number, since it uses as much as digits as its factorization.

131205987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1262 (or 1231 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 36.

The square root of 131205987 is about 11454.5181915260. The cubic root of 131205987 is about 508.1413661481.

The spelling of 131205987 in words is "one hundred thirty-one million, two hundred five thousand, nine hundred eighty-seven".