11611143561 has 16 divisors (see below), whose sum is σ = 16337422400. Its totient is φ = 7314867648.

The previous prime is 11611143559. The next prime is 11611143563. The reversal of 11611143561 is 16534111611.

It is an interprime number because it is at equal distance from previous prime (11611143559) and next prime (11611143563).

It is not a de Polignac number, because 11611143561 - 2¹ = 11611143559 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11611143563) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 233926 + ... + 279183.

It is an arithmetic number, because the mean of its divisors is an integer number (1021088900).

Almost surely, 2^11611143561 is an apocalyptic number.

It is an amenable number.

11611143561 is a deficient number, since it is larger than the sum of its proper divisors (4726278839).

11611143561 is a wasteful number, since it uses less digits than its factorization.

11611143561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 513528.

The product of its digits is 2160, while the sum is 30.

The spelling of 11611143561 in words is "eleven billion, six hundred eleven million, one hundred forty-three thousand, five hundred sixty-one".