7997021218 has 16 divisors (see below), whose sum is σ = 12295336536. Its totient is φ = 3898690560.

The previous prime is 7997021213. The next prime is 7997021239. The reversal of 7997021218 is 8121207997.

It can be written as a sum of positive squares in 4 ways, for example, as 996854329 + 7000166889 = 31573^2 + 83667^2 .

It is a super-2 number, since 2×7997021218² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (7997021213) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 115930 + ... + 171562.

Almost surely, 2^7997021218 is an apocalyptic number.

7997021218 is a deficient number, since it is larger than the sum of its proper divisors (4298315318).

7997021218 is a wasteful number, since it uses less digits than its factorization.

7997021218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57429.

The product of its (nonzero) digits is 127008, while the sum is 46.

The square root of 7997021218 is about 89426.0656520234. The cubic root of 7997021218 is about 1999.7517373508.

The spelling of 7997021218 in words is "seven billion, nine hundred ninety-seven million, twenty-one thousand, two hundred eighteen".