87521157 has 6 divisors (see below), whose sum is σ = 126419462. Its totient is φ = 58347432.

The previous prime is 87521149. The next prime is 87521221. The reversal of 87521157 is 75112578.

87521157 is a `hidden beast` number, since 87 + 521 + 1 + 57 = 666.

It can be written as a sum of positive squares in only one way, i.e., 61449921 + 26071236 = 7839^2 + 5106^2 .

It is not a de Polignac number, because 87521157 - 2³ = 87521149 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 (87525157) 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, 4862278 + ... + 4862295.

Almost surely, 2^87521157 is an apocalyptic number.

It is an amenable number.

87521157 is a deficient number, since it is larger than the sum of its proper divisors (38898305).

87521157 is a wasteful number, since it uses less digits than its factorization.

87521157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9724579 (or 9724576 counting only the distinct ones).

The product of its digits is 19600, while the sum is 36.

The square root of 87521157 is about 9355.2742878015. The cubic root of 87521157 is about 443.9877796734.

It can be divided in two parts, 87521 and 157, that added together give a palindrome (87678).

The spelling of 87521157 in words is "eighty-seven million, five hundred twenty-one thousand, one hundred fifty-seven".