77656320 has 360 divisors, whose sum is σ = 320531904. Its totient is φ = 17584128.

The previous prime is 77656307. The next prime is 77656343. The reversal of 77656320 is 2365677.

It is a happy number.

77656320 is a `hidden beast` number, since 7 + 76 + 563 + 20 = 666.

It is a tau number, because it is divible by the number of its divisors (360).

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

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 725707 + ... + 725813.

Almost surely, 2^77656320 is an apocalyptic number.

77656320 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 77656320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (160265952).

77656320 is an abundant number, since it is smaller than the sum of its proper divisors (242875584).

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

77656320 is a wasteful number, since it uses less digits than its factorization.

77656320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147 (or 124 counting only the distinct ones).

The product of its (nonzero) digits is 52920, while the sum is 36.

The square root of 77656320 is about 8812.2823377375. The cubic root of 77656320 is about 426.6374111885.

The spelling of 77656320 in words is "seventy-seven million, six hundred fifty-six thousand, three hundred twenty".