6618994251 has 32 divisors (see below), whose sum is σ = 9440356608. Its totient is φ = 4110704640.

The previous prime is 6618994231. The next prime is 6618994259. The reversal of 6618994251 is 1524998166.

It is not a de Polignac number, because 6618994251 - 2⁵ = 6618994219 is a prime.

It is a super-2 number, since 2×6618994251² = 87622169789542102002, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a junction number, because it is equal to n+sod(n) for n = 6618994194 and 6618994203.

It is not an unprimeable number, because it can be changed into a prime (6618994259) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2075280 + ... + 2078466.

It is an arithmetic number, because the mean of its divisors is an integer number (295011144).

Almost surely, 2^6618994251 is an apocalyptic number.

6618994251 is a deficient number, since it is larger than the sum of its proper divisors (2821362357).

6618994251 is a wasteful number, since it uses less digits than its factorization.

6618994251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3611.

The product of its digits is 933120, while the sum is 51.

The square root of 6618994251 is about 81357.2015927293. The cubic root of 6618994251 is about 1877.5751757337.

The spelling of 6618994251 in words is "six billion, six hundred eighteen million, nine hundred ninety-four thousand, two hundred fifty-one".