7999215864 has 16 divisors (see below), whose sum is σ = 19998039720. Its totient is φ = 2666405280.

The previous prime is 7999215803. The next prime is 7999215883. The reversal of 7999215864 is 4685129997.

It is a junction number, because it is equal to n+sod(n) for n = 7999215798 and 7999215807.

It is a congruent number.

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, 166650307 + ... + 166650354.

Almost surely, 2^7999215864 is an apocalyptic number.

It is an amenable number.

7999215864 is an abundant number, since it is smaller than the sum of its proper divisors (11998823856).

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

7999215864 is a wasteful number, since it uses less digits than its factorization.

7999215864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 333300670 (or 333300666 counting only the distinct ones).

The product of its digits is 9797760, while the sum is 60.

The square root of 7999215864 is about 89438.3355390741. The cubic root of 7999215864 is about 1999.9346531983.

The spelling of 7999215864 in words is "seven billion, nine hundred ninety-nine million, two hundred fifteen thousand, eight hundred sixty-four".