261421056376650 has 36 divisors (see below), whose sum is σ = 702351238133142. Its totient is φ = 69712281700320.

The previous prime is 261421056376639. The next prime is 261421056376717. The reversal of 261421056376650 is 56673650124162.

261421056376650 is a `hidden beast` number, since 2 + 6 + 1 + 4 + 2 + 1 + 0 + 563 + 76 + 6 + 5 + 0 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 199380528127089 + 62040528249561 = 14120217^2 + 7876581^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 290467839969 + ... + 290467840868.

Almost surely, 2^{261421056376650} is an apocalyptic number.

261421056376650 is an abundant number, since it is smaller than the sum of its proper divisors (440930181756492).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

261421056376650 is a wasteful number, since it uses less digits than its factorization.

261421056376650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 580935680855 (or 580935680847 counting only the distinct ones).

The product of its (nonzero) digits is 10886400, while the sum is 54.

The spelling of 261421056376650 in words is "two hundred sixty-one trillion, four hundred twenty-one billion, fifty-six million, three hundred seventy-six thousand, six hundred fifty".