87991400 has 48 divisors (see below), whose sum is σ = 233809440. Its totient is φ = 30168000.

The previous prime is 87991357. The next prime is 87991441. The reversal of 87991400 is 419978.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 30026 + ... + 32825.

It is an arithmetic number, because the mean of its divisors is an integer number (4871030).

Almost surely, 2^87991400 is an apocalyptic number.

It is an amenable number.

87991400 is an abundant number, since it is smaller than the sum of its proper divisors (145818040).

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

87991400 is a wasteful number, since it uses less digits than its factorization.

87991400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62874 (or 62865 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 38.

The square root of 87991400 is about 9380.3731269071. The cubic root of 87991400 is about 444.7815280746.

The spelling of 87991400 in words is "eighty-seven million, nine hundred ninety-one thousand, four hundred".