11721375617664 has 128 divisors (see below), whose sum is σ = 33091721182080. Its totient is φ = 3663311667200.

The previous prime is 11721375617617. The next prime is 11721375617717. The reversal of 11721375617664 is 46671657312711.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (128).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1696737 + ... + 5130464.

It is an arithmetic number, because the mean of its divisors is an integer number (258529071735).

Almost surely, 2^{11721375617664} is an apocalyptic number.

It is an amenable number.

11721375617664 is an abundant number, since it is smaller than the sum of its proper divisors (21370345564416).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

11721375617664 is a wasteful number, since it uses less digits than its factorization.

11721375617664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6827498 (or 6827486 counting only the distinct ones).

The product of its digits is 8890560, while the sum is 57.

The spelling of 11721375617664 in words is "eleven trillion, seven hundred twenty-one billion, three hundred seventy-five million, six hundred seventeen thousand, six hundred sixty-four".