78315620 has 12 divisors (see below), whose sum is σ = 164462844. Its totient is φ = 31326240.

The previous prime is 78315613. The next prime is 78315647. The reversal of 78315620 is 2651387.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 54967396 + 23348224 = 7414^2 + 4832^2 .

It is a super-2 number, since 2×78315620² = 12266672671968800, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1957871 + ... + 1957910.

It is an arithmetic number, because the mean of its divisors is an integer number (13705237).

Almost surely, 2^78315620 is an apocalyptic number.

It is an amenable number.

78315620 is an abundant number, since it is smaller than the sum of its proper divisors (86147224).

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

78315620 is a wasteful number, since it uses less digits than its factorization.

78315620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3915790 (or 3915788 counting only the distinct ones).

The product of its (nonzero) digits is 10080, while the sum is 32.

The square root of 78315620 is about 8849.6112908986. The cubic root of 78315620 is about 427.8413902640.

The spelling of 78315620 in words is "seventy-eight million, three hundred fifteen thousand, six hundred twenty".