78399792 has 80 divisors (see below), whose sum is σ = 226116480. Its totient is φ = 26008128.

The previous prime is 78399791. The next prime is 78399799. The reversal of 78399792 is 29799387.

It is a super-2 number, since 2×78399792² = 12293054771286528, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (78399791) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 149643 + ... + 150165.

It is an arithmetic number, because the mean of its divisors is an integer number (2826456).

Almost surely, 2^78399792 is an apocalyptic number.

78399792 is a gapful number since it is divisible by the number (72) 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 78399792, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (113058240).

78399792 is an abundant number, since it is smaller than the sum of its proper divisors (147716688).

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

78399792 is a wasteful number, since it uses less digits than its factorization.

78399792 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 887 (or 875 counting only the distinct ones).

The product of its digits is 1714608, while the sum is 54.

The square root of 78399792 is about 8854.3657028609. The cubic root of 78399792 is about 427.9946137267.

The spelling of 78399792 in words is "seventy-eight million, three hundred ninety-nine thousand, seven hundred ninety-two".