11721461521 has 8 divisors (see below), whose sum is σ = 14613770304. Its totient is φ = 9133606320.

The previous prime is 11721461519. The next prime is 11721461569. The reversal of 11721461521 is 12516412711.

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 11721461521 - 2¹ = 11721461519 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11721461321) 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, 76113310 + ... + 76113463.

It is an arithmetic number, because the mean of its divisors is an integer number (1826721288).

Almost surely, 2^11721461521 is an apocalyptic number.

11721461521 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

11721461521 is a deficient number, since it is larger than the sum of its proper divisors (2892308783).

11721461521 is a wasteful number, since it uses less digits than its factorization.

11721461521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 152226791.

The product of its digits is 3360, while the sum is 31.

The spelling of 11721461521 in words is "eleven billion, seven hundred twenty-one million, four hundred sixty-one thousand, five hundred twenty-one".