87431904 has 144 divisors (see below), whose sum is σ = 293529600. Its totient is φ = 24157440.

The previous prime is 87431831. The next prime is 87431921. The reversal of 87431904 is 40913478.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 61797 + ... + 63195.

It is an arithmetic number, because the mean of its divisors is an integer number (2038400).

Almost surely, 2^87431904 is an apocalyptic number.

87431904 is a gapful number since it is divisible by the number (84) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 87431904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (146764800).

87431904 is an abundant number, since it is smaller than the sum of its proper divisors (206097696).

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

87431904 is a wasteful number, since it uses less digits than its factorization.

87431904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1453 (or 1442 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 87431904 is about 9350.5028741774. The cubic root of 87431904 is about 443.8368039141.

The spelling of 87431904 in words is "eighty-seven million, four hundred thirty-one thousand, nine hundred four".