2556404520205 has 16 divisors (see below), whose sum is σ = 3077819057664. Its totient is φ = 2038378020160.

The previous prime is 2556404520169. The next prime is 2556404520281. The reversal of 2556404520205 is 5020254046552.

It is not a de Polignac number, because 2556404520205 - 2²⁵ = 2556370965773 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1380795 + ... + 2649415.

It is an arithmetic number, because the mean of its divisors is an integer number (192363691104).

Almost surely, 2^{2556404520205} is an apocalyptic number.

It is an amenable number.

2556404520205 is a deficient number, since it is larger than the sum of its proper divisors (521414537459).

2556404520205 is a wasteful number, since it uses less digits than its factorization.

2556404520205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1269956.

The product of its (nonzero) digits is 480000, while the sum is 40.

Adding to 2556404520205 its reverse (5020254046552), we get a palindrome (7576658566757).

The spelling of 2556404520205 in words is "two trillion, five hundred fifty-six billion, four hundred four million, five hundred twenty thousand, two hundred five".