87129585 has 12 divisors (see below), whose sum is σ = 151024692. Its totient is φ = 46469088.

The previous prime is 87129577. The next prime is 87129593. The reversal of 87129585 is 58592178.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (87129577) and next prime (87129593).

It can be written as a sum of positive squares in 2 ways, for example, as 18173169 + 68956416 = 4263^2 + 8304^2 .

It is not a de Polignac number, because 87129585 - 2³ = 87129577 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45), and also a Moran number because the ratio is a prime number: 1936213 = 87129585 / (8 + 7 + 1 + 2 + 9 + 5 + 8 + 5).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 87129585.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 968062 + ... + 968151.

It is an arithmetic number, because the mean of its divisors is an integer number (12585391).

Almost surely, 2^87129585 is an apocalyptic number.

It is an amenable number.

87129585 is a deficient number, since it is larger than the sum of its proper divisors (63895107).

87129585 is a wasteful number, since it uses less digits than its factorization.

87129585 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1936224 (or 1936221 counting only the distinct ones).

The product of its digits is 201600, while the sum is 45.

The square root of 87129585 is about 9334.3229534873. The cubic root of 87129585 is about 443.3246519993.

The spelling of 87129585 in words is "eighty-seven million, one hundred twenty-nine thousand, five hundred eighty-five".