77908320 has 288 divisors, whose sum is σ = 311351040. Its totient is φ = 17372160.

The previous prime is 77908309. The next prime is 77908321. The reversal of 77908320 is 2380977.

It is a tau number, because it is divible by the number of its divisors (288).

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77908321) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 594655 + ... + 594785.

It is an arithmetic number, because the mean of its divisors is an integer number (1081080).

Almost surely, 2^77908320 is an apocalyptic number.

77908320 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 77908320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (155675520).

77908320 is an abundant number, since it is smaller than the sum of its proper divisors (233442720).

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

77908320 is a wasteful number, since it uses less digits than its factorization.

77908320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 218 (or 207 counting only the distinct ones).

The product of its (nonzero) digits is 21168, while the sum is 36.

The square root of 77908320 is about 8826.5689823396. The cubic root of 77908320 is about 427.0984019642.

It can be divided in two parts, 7790 and 8320, that added together give a triangular number (16110 = T₁₇₉).

The spelling of 77908320 in words is "seventy-seven million, nine hundred eight thousand, three hundred twenty".