21621401714216 has 16 divisors (see below), whose sum is σ = 40678490430900. Its totient is φ = 10773804265984.

The previous prime is 21621401714153. The next prime is 21621401714221. The reversal of 21621401714216 is 61241710412612.

It can be written as a sum of positive squares in 2 ways, for example, as 21198160389316 + 423241324900 = 4604146^2 + 650570^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21621401714216.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4612071401 + ... + 4612076088.

Almost surely, 2^{21621401714216} is an apocalyptic number.

It is an amenable number.

21621401714216 is a deficient number, since it is larger than the sum of its proper divisors (19057088716684).

21621401714216 is a wasteful number, since it uses less digits than its factorization.

21621401714216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9224147788 (or 9224147784 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 38.

The spelling of 21621401714216 in words is "twenty-one trillion, six hundred twenty-one billion, four hundred one million, seven hundred fourteen thousand, two hundred sixteen".