77081856 has 72 divisors (see below), whose sum is σ = 206721984. Its totient is φ = 25497600.

The previous prime is 77081831. The next prime is 77081897. The reversal of 77081856 is 65818077.

It is a super-2 number, since 2×77081856² = 11883225048809472, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 127956 + ... + 128556.

Almost surely, 2^77081856 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 77081856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (103360992).

77081856 is an abundant number, since it is smaller than the sum of its proper divisors (129640128).

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

77081856 is a wasteful number, since it uses less digits than its factorization.

77081856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 787 (or 773 counting only the distinct ones).

The product of its (nonzero) digits is 94080, while the sum is 42.

The square root of 77081856 is about 8779.6273269428. The cubic root of 77081856 is about 425.5827871004.

The spelling of 77081856 in words is "seventy-seven million, eighty-one thousand, eight hundred fifty-six".