261170418613 has 4 divisors (see below), whose sum is σ = 281260450828. Its totient is φ = 241080386400.

The previous prime is 261170418589. The next prime is 261170418623. The reversal of 261170418613 is 316814071162.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 71373396964 + 189797021649 = 267158^2 + 435657^2 .

It is a cyclic number.

It is not a de Polignac number, because 261170418613 - 2²¹ = 261168321461 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 (261170418623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10045016088 + ... + 10045016113.

It is an arithmetic number, because the mean of its divisors is an integer number (70315112707).

Almost surely, 2^261170418613 is an apocalyptic number.

It is an amenable number.

261170418613 is a deficient number, since it is larger than the sum of its proper divisors (20090032215).

261170418613 is a wasteful number, since it uses less digits than its factorization.

261170418613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20090032214.

The product of its (nonzero) digits is 48384, while the sum is 40.

Adding to 261170418613 its reverse (316814071162), we get a palindrome (577984489775).

The spelling of 261170418613 in words is "two hundred sixty-one billion, one hundred seventy million, four hundred eighteen thousand, six hundred thirteen".