77927920 has 80 divisors (see below), whose sum is σ = 212718528. Its totient is φ = 25989120.

The previous prime is 77927917. The next prime is 77927939. The reversal of 77927920 is 2972977.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18840 + ... + 22600.

Almost surely, 2^77927920 is an apocalyptic number.

77927920 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 77927920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106359264).

77927920 is an abundant number, since it is smaller than the sum of its proper divisors (134790608).

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

77927920 is a wasteful number, since it uses less digits than its factorization.

77927920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3818 (or 3812 counting only the distinct ones).

The product of its (nonzero) digits is 111132, while the sum is 43.

The square root of 77927920 is about 8827.6791967085. The cubic root of 77927920 is about 427.1342151130.

The spelling of 77927920 in words is "seventy-seven million, nine hundred twenty-seven thousand, nine hundred twenty".