7991216618 has 16 divisors (see below), whose sum is σ = 14944613184. Its totient is φ = 3113460960.

The previous prime is 7991216617. The next prime is 7991216663. The reversal of 7991216618 is 8166121997.

It is not an unprimeable number, because it can be changed into a prime (7991216617) 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, 25945355 + ... + 25945662.

It is an arithmetic number, because the mean of its divisors is an integer number (934038324).

Almost surely, 2^7991216618 is an apocalyptic number.

7991216618 is a deficient number, since it is larger than the sum of its proper divisors (6953396566).

7991216618 is a wasteful number, since it uses less digits than its factorization.

7991216618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51891037.

The product of its digits is 326592, while the sum is 50.

The square root of 7991216618 is about 89393.6050173613. The cubic root of 7991216618 is about 1999.2677834622.

The spelling of 7991216618 in words is "seven billion, nine hundred ninety-one million, two hundred sixteen thousand, six hundred eighteen".