87639040 has 44 divisors (see below), whose sum is σ = 210243276. Its totient is φ = 35053568.

The previous prime is 87639023. The next prime is 87639049. The reversal of 87639040 is 4093678.

It can be written as a sum of positive squares in 2 ways, for example, as 9634816 + 78004224 = 3104^2 + 8832^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87639049) 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, 3439 + ... + 13678.

Almost surely, 2^87639040 is an apocalyptic number.

87639040 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

87639040 is an abundant number, since it is smaller than the sum of its proper divisors (122604236).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

87639040 is a wasteful number, since it uses less digits than its factorization.

87639040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17142 (or 17124 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 37.

The square root of 87639040 is about 9361.5725174780. The cubic root of 87639040 is about 444.1870272319.

The spelling of 87639040 in words is "eighty-seven million, six hundred thirty-nine thousand, forty".