21216556663052 has 6 divisors (see below), whose sum is σ = 37128974160348. Its totient is φ = 10608278331524.

The previous prime is 21216556663051. The next prime is 21216556663069. The reversal of 21216556663052 is 25036665561212.

It is not an unprimeable number, because it can be changed into a prime (21216556663051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2652069582878 + ... + 2652069582885.

It is an arithmetic number, because the mean of its divisors is an integer number (6188162360058).

Almost surely, 2^{21216556663052} is an apocalyptic number.

It is an amenable number.

21216556663052 is a deficient number, since it is larger than the sum of its proper divisors (15912417497296).

21216556663052 is a wasteful number, since it uses less digits than its factorization.

21216556663052 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5304139165767 (or 5304139165765 counting only the distinct ones).

The product of its (nonzero) digits is 3888000, while the sum is 50.

The spelling of 21216556663052 in words is "twenty-one trillion, two hundred sixteen billion, five hundred fifty-six million, six hundred sixty-three thousand, fifty-two".