11615320561 has 8 divisors (see below), whose sum is σ = 12578690880. Its totient is φ = 10661933712.

The previous prime is 11615320553. The next prime is 11615320573. The reversal of 11615320561 is 16502351611.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 11615320561 - 2³ = 11615320553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11615320061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2493445 + ... + 2498098.

It is an arithmetic number, because the mean of its divisors is an integer number (1572336360).

Almost surely, 2^11615320561 is an apocalyptic number.

It is an amenable number.

11615320561 is a deficient number, since it is larger than the sum of its proper divisors (963370319).

11615320561 is a wasteful number, since it uses less digits than its factorization.

11615320561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4991735.

The product of its (nonzero) digits is 5400, while the sum is 31.

The spelling of 11615320561 in words is "eleven billion, six hundred fifteen million, three hundred twenty thousand, five hundred sixty-one".