7978694912 has 36 divisors (see below), whose sum is σ = 16033187100. Its totient is φ = 3962554368.

The previous prime is 7978694869. The next prime is 7978694921. The reversal of 7978694912 is 2194968797.

It can be written as a sum of positive squares in 2 ways, for example, as 5055778816 + 2922916096 = 71104^2 + 54064^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66443 + ... + 142730.

Almost surely, 2^7978694912 is an apocalyptic number.

It is an amenable number.

7978694912 is an abundant number, since it is smaller than the sum of its proper divisors (8054492188).

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

7978694912 is a wasteful number, since it uses less digits than its factorization.

7978694912 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 209338 (or 209324 counting only the distinct ones).

The product of its digits is 13716864, while the sum is 62.

The square root of 7978694912 is about 89323.5406373930. The cubic root of 7978694912 is about 1998.2229975988. Note that the first 3 decimals are identical.

The spelling of 7978694912 in words is "seven billion, nine hundred seventy-eight million, six hundred ninety-four thousand, nine hundred twelve".