87637321 has 4 divisors (see below), whose sum is σ = 88622100. Its totient is φ = 86652544.

The previous prime is 87637313. The next prime is 87637327. The reversal of 87637321 is 12373678.

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 61011721 + 26625600 = 7811^2 + 5160^2 .

It is a cyclic number.

It is not a de Polignac number, because 87637321 - 2³ = 87637313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (87637327) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 492256 + ... + 492433.

It is an arithmetic number, because the mean of its divisors is an integer number (22155525).

Almost surely, 2^87637321 is an apocalyptic number.

It is an amenable number.

87637321 is a deficient number, since it is larger than the sum of its proper divisors (984779).

87637321 is an equidigital number, since it uses as much as digits as its factorization.

87637321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 984778.

The product of its digits is 42336, while the sum is 37.

The square root of 87637321 is about 9361.4807055294. The cubic root of 87637321 is about 444.1841230373.

The spelling of 87637321 in words is "eighty-seven million, six hundred thirty-seven thousand, three hundred twenty-one".