78649172 has 24 divisors (see below), whose sum is σ = 157535616. Its totient is φ = 33655968.

The previous prime is 78649163. The next prime is 78649177. The reversal of 78649172 is 27194687.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78649177) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21338 + ... + 24750.

It is an arithmetic number, because the mean of its divisors is an integer number (6563984).

Almost surely, 2^78649172 is an apocalyptic number.

It is an amenable number.

78649172 is an abundant number, since it is smaller than the sum of its proper divisors (78886444).

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

78649172 is a wasteful number, since it uses less digits than its factorization.

78649172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4247 (or 4245 counting only the distinct ones).

The product of its digits is 169344, while the sum is 44.

The square root of 78649172 is about 8868.4368408418. The cubic root of 78649172 is about 428.4479326500.

The spelling of 78649172 in words is "seventy-eight million, six hundred forty-nine thousand, one hundred seventy-two".