11115515661 has 8 divisors (see below), whose sum is σ = 14824337280. Its totient is φ = 7408518912.

The previous prime is 11115515639. The next prime is 11115515669. The reversal of 11115515661 is 16651551111.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 11115515661 - 2⁵ = 11115515629 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11115515669) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 441940 + ... + 466413.

It is an arithmetic number, because the mean of its divisors is an integer number (1853042160).

Almost surely, 2^11115515661 is an apocalyptic number.

It is an amenable number.

11115515661 is a deficient number, since it is larger than the sum of its proper divisors (3708821619).

11115515661 is an equidigital number, since it uses as much as digits as its factorization.

11115515661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 912435.

The product of its digits is 4500, while the sum is 33.

The spelling of 11115515661 in words is "eleven billion, one hundred fifteen million, five hundred fifteen thousand, six hundred sixty-one".