87813831 has 32 divisors (see below), whose sum is σ = 138880000. Its totient is φ = 49321440.

The previous prime is 87813829. The next prime is 87813833. The reversal of 87813831 is 13831878.

It is an interprime number because it is at equal distance from previous prime (87813829) and next prime (87813833).

It is not a de Polignac number, because 87813831 - 2¹ = 87813829 is a prime.

It is a super-2 number, since 2×87813831² = 15422537829793122, which contains 22 as substring.

It is a hoax number, since the sum of its digits (39) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 87813831.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87813833) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 62070 + ... + 63468.

It is an arithmetic number, because the mean of its divisors is an integer number (4340000).

Almost surely, 2^87813831 is an apocalyptic number.

87813831 is a deficient number, since it is larger than the sum of its proper divisors (51066169).

87813831 is a wasteful number, since it uses less digits than its factorization.

87813831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1484 (or 1470 counting only the distinct ones).

The product of its digits is 32256, while the sum is 39.

The square root of 87813831 is about 9370.9034249639. The cubic root of 87813831 is about 444.4821329128.

The spelling of 87813831 in words is "eighty-seven million, eight hundred thirteen thousand, eight hundred thirty-one".