7997667998 has 4 divisors (see below), whose sum is σ = 11996502000. Its totient is φ = 3998833998.

The previous prime is 7997667989. The next prime is 7997668033. The reversal of 7997667998 is 8997667997.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1999416998 + ... + 1999417001.

It is an arithmetic number, because the mean of its divisors is an integer number (2999125500).

Almost surely, 2^7997667998 is an apocalyptic number.

7997667998 is a deficient number, since it is larger than the sum of its proper divisors (3998834002).

7997667998 is a wasteful number, since it uses less digits than its factorization.

7997667998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3998834001.

The product of its digits is 648121824, while the sum is 77.

The square root of 7997667998 is about 89429.6818623437. The cubic root of 7997667998 is about 1999.8056476142.

Subtracting 7997667998 from its reverse (8997667997), we obtain a palindrome (999999999).

The spelling of 7997667998 in words is "seven billion, nine hundred ninety-seven million, six hundred sixty-seven thousand, nine hundred ninety-eight".