78739331938 has 4 divisors (see below), whose sum is σ = 118108997910. Its totient is φ = 39369665968.

The previous prime is 78739331929. The next prime is 78739331963. The reversal of 78739331938 is 83913393787.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 47712975489 + 31026356449 = 218433^2 + 176143^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19684832983 + ... + 19684832986.

Almost surely, 2^78739331938 is an apocalyptic number.

78739331938 is a deficient number, since it is larger than the sum of its proper divisors (39369665972).

78739331938 is a wasteful number, since it uses less digits than its factorization.

78739331938 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39369665971.

The product of its digits is 20575296, while the sum is 61.

The spelling of 78739331938 in words is "seventy-eight billion, seven hundred thirty-nine million, three hundred thirty-one thousand, nine hundred thirty-eight".