261656230514021 has 16 divisors (see below), whose sum is σ = 317582600987520. Its totient is φ = 210446301795840.

The previous prime is 261656230513999. The next prime is 261656230514027. The reversal of 261656230514021 is 120415032656162.

It is a cyclic number.

It is not a de Polignac number, because 261656230514021 - 2⁶ = 261656230513957 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261656230514027) 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, 3321398456 + ... + 3321477233.

It is an arithmetic number, because the mean of its divisors is an integer number (19848912561720).

Almost surely, 2^{261656230514021} is an apocalyptic number.

It is an amenable number.

261656230514021 is a deficient number, since it is larger than the sum of its proper divisors (55926370473499).

261656230514021 is a wasteful number, since it uses less digits than its factorization.

261656230514021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6642876044.

The product of its (nonzero) digits is 518400, while the sum is 44.

The spelling of 261656230514021 in words is "two hundred sixty-one trillion, six hundred fifty-six billion, two hundred thirty million, five hundred fourteen thousand, twenty-one".