261461659193 has 4 divisors (see below), whose sum is σ = 298813324800. Its totient is φ = 224109993588.

The previous prime is 261461659189. The next prime is 261461659253. The reversal of 261461659193 is 391956164162.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 261461659193 - 2² = 261461659189 is a prime.

It is a super-2 number, since 2×261461659193² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (261461659153) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18675832793 + ... + 18675832806.

It is an arithmetic number, because the mean of its divisors is an integer number (74703331200).

Almost surely, 2^261461659193 is an apocalyptic number.

It is an amenable number.

261461659193 is a deficient number, since it is larger than the sum of its proper divisors (37351665607).

261461659193 is an equidigital number, since it uses as much as digits as its factorization.

261461659193 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37351665606.

The product of its digits is 2099520, while the sum is 53.

The spelling of 261461659193 in words is "two hundred sixty-one billion, four hundred sixty-one million, six hundred fifty-nine thousand, one hundred ninety-three".