77220864 has 330 divisors, whose sum is σ = 282363180. Its totient is φ = 20901888.

The previous prime is 77220811. The next prime is 77220893. The reversal of 77220864 is 46802277.

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 29 ways as a sum of consecutive naturals, for example, 4064247 + ... + 4064265.

It is an arithmetic number, because the mean of its divisors is an integer number (855646).

Almost surely, 2^77220864 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 77220864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (141181590).

77220864 is an abundant number, since it is smaller than the sum of its proper divisors (205142316).

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

77220864 is a wasteful number, since it uses less digits than its factorization.

77220864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65 (or 31 counting only the distinct ones).

The product of its (nonzero) digits is 37632, while the sum is 36.

The square root of 77220864 is about 8787.5402701780. The cubic root of 77220864 is about 425.8384628560.

The spelling of 77220864 in words is "seventy-seven million, two hundred twenty thousand, eight hundred sixty-four".