87738521 has 4 divisors (see below), whose sum is σ = 94487652. Its totient is φ = 80989392.

The previous prime is 87738517. The next prime is 87738527. The reversal of 87738521 is 12583778.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 23658496 + 64080025 = 4864^2 + 8005^2 .

It is a cyclic number.

It is not a de Polignac number, because 87738521 - 2² = 87738517 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (87738527) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3374546 + ... + 3374571.

It is an arithmetic number, because the mean of its divisors is an integer number (23621913).

Almost surely, 2^87738521 is an apocalyptic number.

It is an amenable number.

87738521 is a deficient number, since it is larger than the sum of its proper divisors (6749131).

87738521 is a wasteful number, since it uses less digits than its factorization.

87738521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6749130.

The product of its digits is 94080, while the sum is 41.

The square root of 87738521 is about 9366.8842738661. The cubic root of 87738521 is about 444.3550324974.

The spelling of 87738521 in words is "eighty-seven million, seven hundred thirty-eight thousand, five hundred twenty-one".