87137831 has 4 divisors (see below), whose sum is σ = 95059464. Its totient is φ = 79216200.

The previous prime is 87137797. The next prime is 87137873. The reversal of 87137831 is 13873178.

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

It is a cyclic number.

It is not a de Polignac number, because 87137831 - 2¹⁸ = 86875687 is a prime.

It is a super-2 number, since 2×87137831² = 15186003182769122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87137881) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3960800 + ... + 3960821.

It is an arithmetic number, because the mean of its divisors is an integer number (23764866).

Almost surely, 2^87137831 is an apocalyptic number.

87137831 is a deficient number, since it is larger than the sum of its proper divisors (7921633).

87137831 is a wasteful number, since it uses less digits than its factorization.

87137831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7921632.

The product of its digits is 28224, while the sum is 38.

The square root of 87137831 is about 9334.7646462029. The cubic root of 87137831 is about 443.3386370682.

The spelling of 87137831 in words is "eighty-seven million, one hundred thirty-seven thousand, eight hundred thirty-one".