2556638487 has 48 divisors (see below), whose sum is σ = 4081036960. Its totient is φ = 1532369664.

The previous prime is 2556638471. The next prime is 2556638507. The reversal of 2556638487 is 7848366552.

2556638487 is a `hidden beast` number, since 2 + 5 + 566 + 38 + 48 + 7 = 666.

It is not a de Polignac number, because 2556638487 - 2⁴ = 2556638471 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2556638407) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3083589 + ... + 3084417.

Almost surely, 2^2556638487 is an apocalyptic number.

2556638487 is a deficient number, since it is larger than the sum of its proper divisors (1524398473).

2556638487 is a wasteful number, since it uses less digits than its factorization.

2556638487 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1504 (or 1501 counting only the distinct ones).

The product of its digits is 9676800, while the sum is 54.

The square root of 2556638487 is about 50563.2127836039. The cubic root of 2556638487 is about 1367.3817339934.

The spelling of 2556638487 in words is "two billion, five hundred fifty-six million, six hundred thirty-eight thousand, four hundred eighty-seven".