78278984 has 16 divisors (see below), whose sum is σ = 167740800. Its totient is φ = 33548112.

The previous prime is 78278951. The next prime is 78278989. The reversal of 78278984 is 48987287.

It is a happy number.

It is a super-2 number, since 2×78278984² = 12255198672144512, which contains 22 as substring.

It is a Smith number, since the sum of its digits (53) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (78278989) 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 3 ways as a sum of consecutive naturals, for example, 698864 + ... + 698975.

It is an arithmetic number, because the mean of its divisors is an integer number (10483800).

Almost surely, 2^78278984 is an apocalyptic number.

It is an amenable number.

78278984 is an abundant number, since it is smaller than the sum of its proper divisors (89461816).

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

78278984 is a wasteful number, since it uses less digits than its factorization.

78278984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1397852 (or 1397848 counting only the distinct ones).

The product of its digits is 1806336, while the sum is 53.

The square root of 78278984 is about 8847.5411273415. The cubic root of 78278984 is about 427.7746652098.

The spelling of 78278984 in words is "seventy-eight million, two hundred seventy-eight thousand, nine hundred eighty-four".