87000813 has 6 divisors (see below), whose sum is σ = 125667854. Its totient is φ = 58000536.

The previous prime is 87000799. The next prime is 87000833. The reversal of 87000813 is 31800078.

It can be written as a sum of positive squares in only one way, i.e., 69006249 + 17994564 = 8307^2 + 4242^2 .

It is not a de Polignac number, because 87000813 - 2⁹ = 87000301 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87000833) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4833370 + ... + 4833387.

Almost surely, 2^87000813 is an apocalyptic number.

It is an amenable number.

87000813 is a deficient number, since it is larger than the sum of its proper divisors (38667041).

87000813 is a wasteful number, since it uses less digits than its factorization.

87000813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9666763 (or 9666760 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 27.

The square root of 87000813 is about 9327.4226343615. The cubic root of 87000813 is about 443.1061424109.

The spelling of 87000813 in words is "eighty-seven million, eight hundred thirteen", and thus it is an aban number.