87781904 has 20 divisors (see below), whose sum is σ = 194374464. Its totient is φ = 37620768.

The previous prime is 87781901. The next prime is 87781907. The reversal of 87781904 is 40918778.

It is an interprime number because it is at equal distance from previous prime (87781901) and next prime (87781907).

It is not an unprimeable number, because it can be changed into a prime (87781901) 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, 391772 + ... + 391995.

Almost surely, 2^87781904 is an apocalyptic number.

It is an amenable number.

87781904 is an abundant number, since it is smaller than the sum of its proper divisors (106592560).

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

87781904 is a wasteful number, since it uses less digits than its factorization.

87781904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 783782 (or 783776 counting only the distinct ones).

The product of its (nonzero) digits is 112896, while the sum is 44.

The square root of 87781904 is about 9369.1997523801. The cubic root of 87781904 is about 444.4282587069.

The spelling of 87781904 in words is "eighty-seven million, seven hundred eighty-one thousand, nine hundred four".