78891964 has 24 divisors (see below), whose sum is σ = 140652288. Its totient is φ = 38710320.

The previous prime is 78891949. The next prime is 78891973. The reversal of 78891964 is 46919887.

It is a happy number.

It is a congruent number.

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, 115167 + ... + 115849.

It is an arithmetic number, because the mean of its divisors is an integer number (5860512).

Almost surely, 2^78891964 is an apocalyptic number.

It is an amenable number.

78891964 is a deficient number, since it is larger than the sum of its proper divisors (61760324).

78891964 is a wasteful number, since it uses less digits than its factorization.

78891964 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1185 (or 1183 counting only the distinct ones).

The product of its digits is 870912, while the sum is 52.

The square root of 78891964 is about 8882.1148382578. The cubic root of 78891964 is about 428.8883563261. Note that the first 3 decimals are identical.

The spelling of 78891964 in words is "seventy-eight million, eight hundred ninety-one thousand, nine hundred sixty-four".