11956555761 has 4 divisors (see below), whose sum is σ = 15942074352. Its totient is φ = 7971037172.

The previous prime is 11956555759. The next prime is 11956555769. The reversal of 11956555761 is 16755565911.

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 11956555761 - 2¹ = 11956555759 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11956555769) 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, 1992759291 + ... + 1992759296.

It is an arithmetic number, because the mean of its divisors is an integer number (3985518588).

Almost surely, 2^11956555761 is an apocalyptic number.

It is an amenable number.

11956555761 is a deficient number, since it is larger than the sum of its proper divisors (3985518591).

11956555761 is an equidigital number, since it uses as much as digits as its factorization.

11956555761 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3985518590.

The product of its digits is 1417500, while the sum is 51.

The spelling of 11956555761 in words is "eleven billion, nine hundred fifty-six million, five hundred fifty-five thousand, seven hundred sixty-one".