78820900 has 18 divisors (see below), whose sum is σ = 171041570. Its totient is φ = 31528320.

The previous prime is 78820897. The next prime is 78820913. The reversal of 78820900 is 902887.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 5410276 + 73410624 = 2326^2 + 8568^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 394005 + ... + 394204.

Almost surely, 2^78820900 is an apocalyptic number.

It is an amenable number.

78820900 is an abundant number, since it is smaller than the sum of its proper divisors (92220670).

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

78820900 is a wasteful number, since it uses less digits than its factorization.

78820900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 788223 (or 788216 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 34.

The square root of 78820900 is about 8878.1135383594. The cubic root of 78820900 is about 428.7595401720.

The spelling of 78820900 in words is "seventy-eight million, eight hundred twenty thousand, nine hundred".