6638816212718 has 4 divisors (see below), whose sum is σ = 9958224319080. Its totient is φ = 3319408106358.

The previous prime is 6638816212667. The next prime is 6638816212747. The reversal of 6638816212718 is 8172126188366.

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, 1659704053178 + ... + 1659704053181.

It is an arithmetic number, because the mean of its divisors is an integer number (2489556079770).

Almost surely, 2^{6638816212718} is an apocalyptic number.

6638816212718 is a deficient number, since it is larger than the sum of its proper divisors (3319408106362).

6638816212718 is a wasteful number, since it uses less digits than its factorization.

6638816212718 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3319408106361.

The product of its digits is 9289728, while the sum is 59.

The spelling of 6638816212718 in words is "six trillion, six hundred thirty-eight billion, eight hundred sixteen million, two hundred twelve thousand, seven hundred eighteen".