78438969 has 32 divisors (see below), whose sum is σ = 140624640. Its totient is φ = 42183936.

The previous prime is 78438967. The next prime is 78438989. The reversal of 78438969 is 96983487.

It is not a de Polignac number, because 78438969 - 2¹ = 78438967 is a prime.

It is a super-2 number, since 2×78438969² = 12305343715565922, which contains 22 as substring.

It is a Curzon number.

It is a plaindrome in base 13.

It is not an unprimeable number, because it can be changed into a prime (78438967) 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 31 ways as a sum of consecutive naturals, for example, 8994 + ... + 15419.

It is an arithmetic number, because the mean of its divisors is an integer number (4394520).

Almost surely, 2^78438969 is an apocalyptic number.

It is an amenable number.

78438969 is a deficient number, since it is larger than the sum of its proper divisors (62185671).

78438969 is a wasteful number, since it uses less digits than its factorization.

78438969 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24446 (or 24440 counting only the distinct ones).

The product of its digits is 2612736, while the sum is 54.

The square root of 78438969 is about 8856.5777250584. The cubic root of 78438969 is about 428.0658926267.

The spelling of 78438969 in words is "seventy-eight million, four hundred thirty-eight thousand, nine hundred sixty-nine".