2557666198 has 4 divisors (see below), whose sum is σ = 3836499300. Its totient is φ = 1278833098.

The previous prime is 2557666117. The next prime is 2557666213. The reversal of 2557666198 is 8916667552.

2557666198 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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, 639416548 + ... + 639416551.

It is an arithmetic number, because the mean of its divisors is an integer number (959124825).

Almost surely, 2^2557666198 is an apocalyptic number.

2557666198 is a deficient number, since it is larger than the sum of its proper divisors (1278833102).

2557666198 is a wasteful number, since it uses less digits than its factorization.

2557666198 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1278833101.

The product of its digits is 5443200, while the sum is 55.

The square root of 2557666198 is about 50573.3743979972. The cubic root of 2557666198 is about 1367.5649283196.

The spelling of 2557666198 in words is "two billion, five hundred fifty-seven million, six hundred sixty-six thousand, one hundred ninety-eight".