79978000 has 40 divisors (see below), whose sum is σ = 193391640. Its totient is φ = 31990400.

The previous prime is 79977983. The next prime is 79978001. The reversal of 79978000 is 87997.

It can be written as a sum of positive squares in 4 ways, for example, as 12278016 + 67699984 = 3504^2 + 8228^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (40).

It is not an unprimeable number, because it can be changed into a prime (79978001) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17995 + ... + 21994.

It is an arithmetic number, because the mean of its divisors is an integer number (4834791).

Almost surely, 2^79978000 is an apocalyptic number.

It is an amenable number.

79978000 is an abundant number, since it is smaller than the sum of its proper divisors (113413640).

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

79978000 is a wasteful number, since it uses less digits than its factorization.

79978000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40012 (or 39996 counting only the distinct ones).

The product of its (nonzero) digits is 31752, while the sum is 40.

The square root of 79978000 is about 8943.0419880486. The cubic root of 79978000 is about 430.8474364159.

The spelling of 79978000 in words is "seventy-nine million, nine hundred seventy-eight thousand".