77313720 has 128 divisors (see below), whose sum is σ = 260029440. Its totient is φ = 18224640.

The previous prime is 77313701. The next prime is 77313727. The reversal of 77313720 is 2731377.

It is a super-2 number, since 2×77313720² = 11954822600476800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77313727) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 48049 + ... + 49631.

It is an arithmetic number, because the mean of its divisors is an integer number (2031480).

Almost surely, 2^77313720 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 77313720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (130014720).

77313720 is an abundant number, since it is smaller than the sum of its proper divisors (182715720).

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

77313720 is a wasteful number, since it uses less digits than its factorization.

77313720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1645 (or 1641 counting only the distinct ones).

The product of its (nonzero) digits is 6174, while the sum is 30.

The square root of 77313720 is about 8792.8220725772. The cubic root of 77313720 is about 426.0090808970.

The spelling of 77313720 in words is "seventy-seven million, three hundred thirteen thousand, seven hundred twenty".