78785191972 has 12 divisors (see below), whose sum is σ = 137922364300. Its totient is φ = 39378802176.

The previous prime is 78785191889. The next prime is 78785191973. The reversal of 78785191972 is 27919158787.

It can be written as a sum of positive squares in 2 ways, for example, as 55707328576 + 23077863396 = 236024^2 + 151914^2 .

It is a hoax number, since the sum of its digits (64) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (78785191973) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3435597 + ... + 3458452.

Almost surely, 2^78785191972 is an apocalyptic number.

It is an amenable number.

78785191972 is a deficient number, since it is larger than the sum of its proper divisors (59137172328).

78785191972 is a wasteful number, since it uses less digits than its factorization.

78785191972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6896910 (or 6896908 counting only the distinct ones).

The product of its digits is 17781120, while the sum is 64.

The spelling of 78785191972 in words is "seventy-eight billion, seven hundred eighty-five million, one hundred ninety-one thousand, nine hundred seventy-two".