77980356 has 18 divisors (see below), whose sum is σ = 197117102. Its totient is φ = 25993440.

The previous prime is 77980321. The next prime is 77980361. The reversal of 77980356 is 65308977.

It is a happy number.

77980356 is digitally balanced in base 9, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 40525956 + 37454400 = 6366^2 + 6120^2 .

It is a tau number, because it is divible by the number of its divisors (18).

77980356 is strictly pandigital in base 9.

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, 1083025 + ... + 1083096.

Almost surely, 2^77980356 is an apocalyptic number.

It is an amenable number.

77980356 is an abundant number, since it is smaller than the sum of its proper divisors (119136746).

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

77980356 is a wasteful number, since it uses less digits than its factorization.

77980356 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2166131 (or 2166126 counting only the distinct ones).

The product of its (nonzero) digits is 317520, while the sum is 45.

The square root of 77980356 is about 8830.6486737951. The cubic root of 77980356 is about 427.2299967364.

The spelling of 77980356 in words is "seventy-seven million, nine hundred eighty thousand, three hundred fifty-six".