87537281689 has 27 divisors (see below), whose sum is σ = 104239823709. Its totient is φ = 73422354720.

The previous prime is 87537281683. The next prime is 87537281693. The reversal of 87537281689 is 98618273578.

It is a happy number.

The square root of 87537281689 is 295867.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 42335120025 + 45202161664 = 205755^2 + 212608^2 .

It is not a de Polignac number, because 87537281689 - 2⁷ = 87537281561 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 87537281689.

It is not an unprimeable number, because it can be changed into a prime (87537281683) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 42307947 + ... + 42310015.

Almost surely, 2^87537281689 is an apocalyptic number.

87537281689 is the 295867-th square number.

87537281689 is the 147934-th centered octagonal number.

It is an amenable number.

87537281689 is a deficient number, since it is larger than the sum of its proper divisors (16702542020).

87537281689 is an equidigital number, since it uses as much as digits as its factorization.

87537281689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4186 (or 2093 counting only the distinct ones).

The product of its digits is 40642560, while the sum is 64.

Multiplying 87537281689 by its sum of digits (64), we get a square (5602386028096 = 2366936²).

The spelling of 87537281689 in words is "eighty-seven billion, five hundred thirty-seven million, two hundred eighty-one thousand, six hundred eighty-nine".