78886644 has 12 divisors (see below), whose sum is σ = 184068864. Its totient is φ = 26295544.

The previous prime is 78886637. The next prime is 78886649. The reversal of 78886644 is 44668887.

It is a tau number, because it is divible by the number of its divisors (12).

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78886649) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3286932 + ... + 3286955.

It is an arithmetic number, because the mean of its divisors is an integer number (15339072).

Almost surely, 2^78886644 is an apocalyptic number.

It is an amenable number.

78886644 is an abundant number, since it is smaller than the sum of its proper divisors (105182220).

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

78886644 is a wasteful number, since it uses less digits than its factorization.

78886644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6573894 (or 6573892 counting only the distinct ones).

The product of its digits is 2064384, while the sum is 51.

The square root of 78886644 is about 8881.8153549823. The cubic root of 78886644 is about 428.8787155582.

The spelling of 78886644 in words is "seventy-eight million, eight hundred eighty-six thousand, six hundred forty-four".