11811509601 has 4 divisors (see below), whose sum is σ = 15748679472. Its totient is φ = 7874339732.

The previous prime is 11811509597. The next prime is 11811509603. The reversal of 11811509601 is 10690511811.

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 11811509601 - 2² = 11811509597 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11811509603) 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, 1968584931 + ... + 1968584936.

It is an arithmetic number, because the mean of its divisors is an integer number (3937169868).

Almost surely, 2^11811509601 is an apocalyptic number.

It is an amenable number.

11811509601 is a deficient number, since it is larger than the sum of its proper divisors (3937169871).

11811509601 is an equidigital number, since it uses as much as digits as its factorization.

11811509601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3937169870.

The product of its (nonzero) digits is 2160, while the sum is 33.

The spelling of 11811509601 in words is "eleven billion, eight hundred eleven million, five hundred nine thousand, six hundred one".