15664521216 has 224 divisors, whose sum is σ = 44666611200. Its totient is φ = 4871946240.

The previous prime is 15664521167. The next prime is 15664521221. The reversal of 15664521216 is 61212546651.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22093470 + ... + 22094178.

Almost surely, 2^15664521216 is an apocalyptic number.

15664521216 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 15664521216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22333305600).

15664521216 is an abundant number, since it is smaller than the sum of its proper divisors (29002089984).

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

15664521216 is an equidigital number, since it uses as much as digits as its factorization.

15664521216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 798 (or 774 counting only the distinct ones).

The product of its digits is 86400, while the sum is 39.

The spelling of 15664521216 in words is "fifteen billion, six hundred sixty-four million, five hundred twenty-one thousand, two hundred sixteen".