7971562816 has 28 divisors (see below), whose sum is σ = 18078366688. Its totient is φ = 3416383872.

The previous prime is 7971562813. The next prime is 7971562829. The reversal of 7971562816 is 6182651797.

It is a tau number, because it is divible by the number of its divisors (28).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7971562813) 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, 8896386 + ... + 8897281.

Almost surely, 2^7971562816 is an apocalyptic number.

It is an amenable number.

7971562816 is an abundant number, since it is smaller than the sum of its proper divisors (10106803872).

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

7971562816 is a wasteful number, since it uses less digits than its factorization.

7971562816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17793686 (or 17793676 counting only the distinct ones).

The product of its digits is 1270080, while the sum is 52.

The square root of 7971562816 is about 89283.6088876340. The cubic root of 7971562816 is about 1997.6274212146.

The spelling of 7971562816 in words is "seven billion, nine hundred seventy-one million, five hundred sixty-two thousand, eight hundred sixteen".