77953680 has 120 divisors (see below), whose sum is σ = 299212992. Its totient is φ = 17816832.

The previous prime is 77953663. The next prime is 77953697. The reversal of 77953680 is 8635977.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (77953663) and next prime (77953697).

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2694 + ... + 12773.

Almost surely, 2^77953680 is an apocalyptic number.

77953680 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 77953680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (149606496).

77953680 is an abundant number, since it is smaller than the sum of its proper divisors (221259312).

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

77953680 is a wasteful number, since it uses less digits than its factorization.

77953680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15493 (or 15484 counting only the distinct ones).

The product of its (nonzero) digits is 317520, while the sum is 45.

The square root of 77953680 is about 8829.1381232825. The cubic root of 77953680 is about 427.1812746916.

The spelling of 77953680 in words is "seventy-seven million, nine hundred fifty-three thousand, six hundred eighty".