11611421765 has 4 divisors (see below), whose sum is σ = 13933706124. Its totient is φ = 9289137408.

The previous prime is 11611421749. The next prime is 11611421779. The reversal of 11611421765 is 56712411611.

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 3144293476 + 8467128289 = 56074^2 + 92017^2 .

It is a cyclic number.

It is not a de Polignac number, because 11611421765 - 2⁴ = 11611421749 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1161142172 + ... + 1161142181.

It is an arithmetic number, because the mean of its divisors is an integer number (3483426531).

Almost surely, 2^11611421765 is an apocalyptic number.

It is an amenable number.

11611421765 is a deficient number, since it is larger than the sum of its proper divisors (2322284359).

11611421765 is an equidigital number, since it uses as much as digits as its factorization.

11611421765 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2322284358.

The product of its digits is 10080, while the sum is 35.

The spelling of 11611421765 in words is "eleven billion, six hundred eleven million, four hundred twenty-one thousand, seven hundred sixty-five".