261421121132717 has 32 divisors (see below), whose sum is σ = 325088168396544. Its totient is φ = 204692417280000.

The previous prime is 261421121132681. The next prime is 261421121132723. The reversal of 261421121132717 is 717231121124162.

It is not a de Polignac number, because 261421121132717 - 2²² = 261421116938413 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261421121132797) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 129825842 + ... + 131824092.

It is an arithmetic number, because the mean of its divisors is an integer number (10159005262392).

Almost surely, 2^{261421121132717} is an apocalyptic number.

It is an amenable number.

261421121132717 is a deficient number, since it is larger than the sum of its proper divisors (63667047263827).

261421121132717 is a wasteful number, since it uses less digits than its factorization.

261421121132717 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2013189.

The product of its digits is 56448, while the sum is 41.

Adding to 261421121132717 its reverse (717231121124162), we get a palindrome (978652242256879).

The spelling of 261421121132717 in words is "two hundred sixty-one trillion, four hundred twenty-one billion, one hundred twenty-one million, one hundred thirty-two thousand, seven hundred seventeen".