11661161555033 has 4 divisors (see below), whose sum is σ = 11945580129588. Its totient is φ = 11376742980480.

The previous prime is 11661161555011. The next prime is 11661161555041. The reversal of 11661161555033 is 33055516116611.

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 3369911975824 + 8291249579209 = 1835732^2 + 2879453^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11661161555033 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (11661161555083) 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, 142209287216 + ... + 142209287297.

It is an arithmetic number, because the mean of its divisors is an integer number (2986395032397).

Almost surely, 2^{11661161555033} is an apocalyptic number.

It is an amenable number.

11661161555033 is a deficient number, since it is larger than the sum of its proper divisors (284418574555).

11661161555033 is an equidigital number, since it uses as much as digits as its factorization.

11661161555033 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 284418574554.

The product of its (nonzero) digits is 243000, while the sum is 44.

The spelling of 11661161555033 in words is "eleven trillion, six hundred sixty-one billion, one hundred sixty-one million, five hundred fifty-five thousand, thirty-three".