2557698649 has 8 divisors (see below), whose sum is σ = 2817843840. Its totient is φ = 2302158000.

The previous prime is 2557698641. The next prime is 2557698653. The reversal of 2557698649 is 9468967552.

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

It is a cyclic number.

It is not a de Polignac number, because 2557698649 - 2³ = 2557698641 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2557698641) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1149969 + ... + 1152190.

It is an arithmetic number, because the mean of its divisors is an integer number (352230480).

Almost surely, 2^2557698649 is an apocalyptic number.

It is an amenable number.

2557698649 is a deficient number, since it is larger than the sum of its proper divisors (260145191).

2557698649 is a wasteful number, since it uses less digits than its factorization.

2557698649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2302271.

The product of its digits is 32659200, while the sum is 61.

The square root of 2557698649 is about 50573.6952278554. The cubic root of 2557698649 is about 1367.5707120639.

The spelling of 2557698649 in words is "two billion, five hundred fifty-seven million, six hundred ninety-eight thousand, six hundred forty-nine".