2551656177421 has 16 divisors (see below), whose sum is σ = 2842991348400. Its totient is φ = 2273917137408.

The previous prime is 2551656177407. The next prime is 2551656177463. The reversal of 2551656177421 is 1247716561552.

2551656177421 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 8 ways, for example, as 15822872521 + 2535833304900 = 125789^2 + 1592430^2 .

It is a cyclic number.

It is not a de Polignac number, because 2551656177421 - 2⁷ = 2551656177293 is a prime.

It is a super-2 number, since 2×2551656177421² (a number of 26 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2551656177401) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3303475 + ... + 4002031.

It is an arithmetic number, because the mean of its divisors is an integer number (177686959275).

Almost surely, 2^{2551656177421} is an apocalyptic number.

It is an amenable number.

2551656177421 is a deficient number, since it is larger than the sum of its proper divisors (291335170979).

2551656177421 is a wasteful number, since it uses less digits than its factorization.

2551656177421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 708288.

The product of its digits is 3528000, while the sum is 52.

The spelling of 2551656177421 in words is "two trillion, five hundred fifty-one billion, six hundred fifty-six million, one hundred seventy-seven thousand, four hundred twenty-one".