78877421944 has 32 divisors (see below), whose sum is σ = 154574928000. Its totient is φ = 37662986592.

The previous prime is 78877421923. The next prime is 78877421947. The reversal of 78877421944 is 44912477887.

It is a happy number.

It is a Smith number, since the sum of its digits (61) 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 (78877421947) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 232374 + ... + 460165.

It is an arithmetic number, because the mean of its divisors is an integer number (4830466500).

Almost surely, 2^78877421944 is an apocalyptic number.

It is an amenable number.

78877421944 is a deficient number, since it is larger than the sum of its proper divisors (75697506056).

78877421944 is a wasteful number, since it uses less digits than its factorization.

78877421944 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 693187 (or 693183 counting only the distinct ones).

The product of its digits is 25288704, while the sum is 61.

The spelling of 78877421944 in words is "seventy-eight billion, eight hundred seventy-seven million, four hundred twenty-one thousand, nine hundred forty-four".