78979389 has 4 divisors (see below), whose sum is σ = 105305856. Its totient is φ = 52652924.

The previous prime is 78979363. The next prime is 78979391. The reversal of 78979389 is 98397987.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 78979389 - 2¹⁷ = 78848317 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78979189) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13163229 + ... + 13163234.

It is an arithmetic number, because the mean of its divisors is an integer number (26326464).

Almost surely, 2^78979389 is an apocalyptic number.

It is an amenable number.

78979389 is a deficient number, since it is larger than the sum of its proper divisors (26326467).

78979389 is a wasteful number, since it uses less digits than its factorization.

78979389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26326466.

The product of its digits is 6858432, while the sum is 60.

The square root of 78979389 is about 8887.0348823441. The cubic root of 78979389 is about 429.0467236291.

The spelling of 78979389 in words is "seventy-eight million, nine hundred seventy-nine thousand, three hundred eighty-nine".