131287905 has 96 divisors (see below), whose sum is σ = 275788800. Its totient is φ = 59076864.

The previous prime is 131287903. The next prime is 131287913. The reversal of 131287905 is 509782131.

It is not a de Polignac number, because 131287905 - 2¹ = 131287903 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 131287905.

It is not an unprimeable number, because it can be changed into a prime (131287903) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 588624 + ... + 588846.

It is an arithmetic number, because the mean of its divisors is an integer number (2872800).

Almost surely, 2^131287905 is an apocalyptic number.

131287905 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

131287905 is an abundant number, since it is smaller than the sum of its proper divisors (144500895).

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

131287905 is a wasteful number, since it uses less digits than its factorization.

131287905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 340 (or 327 counting only the distinct ones).

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

The square root of 131287905 is about 11458.0934277916. The cubic root of 131287905 is about 508.2470962432.

The spelling of 131287905 in words is "one hundred thirty-one million, two hundred eighty-seven thousand, nine hundred five".