2556638998 has 8 divisors (see below), whose sum is σ = 3835378008. Its totient is φ = 1278179664.

The previous prime is 2556638977. The next prime is 2556639013. The reversal of 2556638998 is 8998366552.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 45336 + ... + 84667.

It is an arithmetic number, because the mean of its divisors is an integer number (479422251).

Almost surely, 2^2556638998 is an apocalyptic number.

2556638998 is a deficient number, since it is larger than the sum of its proper divisors (1278739010).

2556638998 is a wasteful number, since it uses less digits than its factorization.

2556638998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 139838.

The product of its digits is 27993600, while the sum is 61.

The square root of 2556638998 is about 50563.2178366844. The cubic root of 2556638998 is about 1367.3818250938.

The spelling of 2556638998 in words is "two billion, five hundred fifty-six million, six hundred thirty-eight thousand, nine hundred ninety-eight".