78647972 has 24 divisors (see below), whose sum is σ = 151023096. Its totient is φ = 35612928.

The previous prime is 78647957. The next prime is 78647981. The reversal of 78647972 is 27974687.

It can be written as a sum of positive squares in 4 ways, for example, as 784996 + 77862976 = 886^2 + 8824^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 78647972.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11513 + ... + 17024.

It is an arithmetic number, because the mean of its divisors is an integer number (6292629).

Almost surely, 2^78647972 is an apocalyptic number.

It is an amenable number.

78647972 is a deficient number, since it is larger than the sum of its proper divisors (72375124).

78647972 is a wasteful number, since it uses less digits than its factorization.

78647972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28607 (or 28605 counting only the distinct ones).

The product of its digits is 1185408, while the sum is 50.

The square root of 78647972 is about 8868.3691849178. The cubic root of 78647972 is about 428.4457536055.

The spelling of 78647972 in words is "seventy-eight million, six hundred forty-seven thousand, nine hundred seventy-two".