1161261666413 has 4 divisors (see below), whose sum is σ = 1229571176220. Its totient is φ = 1092952156608.

The previous prime is 1161261666353. The next prime is 1161261666419. The reversal of 1161261666413 is 3146661621611.

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 584327234569 + 576934431844 = 764413^2 + 759562^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1161261666413 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 (1161261666419) 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, 34154754878 + ... + 34154754911.

It is an arithmetic number, because the mean of its divisors is an integer number (307392794055).

Almost surely, 2^{1161261666413} is an apocalyptic number.

It is an amenable number.

1161261666413 is a deficient number, since it is larger than the sum of its proper divisors (68309509807).

1161261666413 is an equidigital number, since it uses as much as digits as its factorization.

1161261666413 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68309509806.

The product of its digits is 186624, while the sum is 44.

The spelling of 1161261666413 in words is "one trillion, one hundred sixty-one billion, two hundred sixty-one million, six hundred sixty-six thousand, four hundred thirteen".