78520900 has 36 divisors (see below), whose sum is σ = 170996868. Its totient is φ = 31296640.

The previous prime is 78520867. The next prime is 78520903. The reversal of 78520900 is 902587.

It can be written as a sum of positive squares in 6 ways, for example, as 12716356 + 65804544 = 3566^2 + 8112^2 .

It is not an unprimeable number, because it can be changed into a prime (78520903) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 30462 + ... + 32938.

It is an arithmetic number, because the mean of its divisors is an integer number (4749913).

Almost surely, 2^78520900 is an apocalyptic number.

It is an amenable number.

78520900 is an abundant number, since it is smaller than the sum of its proper divisors (92475968).

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

78520900 is a wasteful number, since it uses less digits than its factorization.

78520900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2808 (or 2801 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 31.

The square root of 78520900 is about 8861.2019500743. The cubic root of 78520900 is about 428.2148817627.

The spelling of 78520900 in words is "seventy-eight million, five hundred twenty thousand, nine hundred".