78522500 has 90 divisors (see below), whose sum is σ = 200059398. Its totient is φ = 26880000.

The previous prime is 78522491. The next prime is 78522527. The reversal of 78522500 is 522587.

It can be written as a sum of positive squares in 5 ways, for example, as 14394436 + 64128064 = 3794^2 + 8008^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 122180 + ... + 122820.

Almost surely, 2^78522500 is an apocalyptic number.

78522500 is a gapful number since it is divisible by the number (70) 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 78522500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (100029699).

78522500 is an abundant number, since it is smaller than the sum of its proper divisors (121536898).

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

78522500 is a wasteful number, since it uses less digits than its factorization.

78522500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 679 (or 655 counting only the distinct ones).

The product of its (nonzero) digits is 5600, while the sum is 29.

The square root of 78522500 is about 8861.2922308205. The cubic root of 78522500 is about 428.2177902841.

The spelling of 78522500 in words is "seventy-eight million, five hundred twenty-two thousand, five hundred".