87655431 has 4 divisors (see below), whose sum is σ = 116873912. Its totient is φ = 58436952.

The previous prime is 87655427. The next prime is 87655441. The reversal of 87655431 is 13455678.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 87655431 - 2² = 87655427 is a prime.

It is a super-2 number, since 2×87655431² = 15366949167591522, which contains 22 as substring.

It is a Duffinian number.

It is a nialpdrome in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 87655431.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87655441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14609236 + ... + 14609241.

It is an arithmetic number, because the mean of its divisors is an integer number (29218478).

Almost surely, 2^87655431 is an apocalyptic number.

87655431 is a deficient number, since it is larger than the sum of its proper divisors (29218481).

87655431 is a wasteful number, since it uses less digits than its factorization.

87655431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29218480.

The product of its digits is 100800, while the sum is 39.

The square root of 87655431 is about 9362.4479170781. The cubic root of 87655431 is about 444.2147173866.

It can be divided in two parts, 8765 and 5431, that added together give a triangular number (14196 = T₁₆₈).

The spelling of 87655431 in words is "eighty-seven million, six hundred fifty-five thousand, four hundred thirty-one".