87291685 has 32 divisors (see below), whose sum is σ = 120349152. Its totient is φ = 60211200.

The previous prime is 87291661. The next prime is 87291697. The reversal of 87291685 is 58619278.

87291685 = 6606² + 6607².

It can be written as a sum of positive squares in 16 ways, for example, as 2024929 + 85266756 = 1423^2 + 9234^2 .

It is not a de Polignac number, because 87291685 - 2⁷ = 87291557 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 217485 + ... + 217885.

It is an arithmetic number, because the mean of its divisors is an integer number (3760911).

Almost surely, 2^87291685 is an apocalyptic number.

87291685 is a gapful number since it is divisible by the number (85) formed by its first and last digit.

87291685 is the 6607-th centered square number.

It is an amenable number.

87291685 is a deficient number, since it is larger than the sum of its proper divisors (33057467).

87291685 is a wasteful number, since it uses less digits than its factorization.

87291685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 633.

The product of its digits is 241920, while the sum is 46.

The square root of 87291685 is about 9343.0019265758. The cubic root of 87291685 is about 443.5994090613.

The spelling of 87291685 in words is "eighty-seven million, two hundred ninety-one thousand, six hundred eighty-five".