21627211564 has 48 divisors (see below), whose sum is σ = 44912750400. Its totient is φ = 8915832576.

The previous prime is 21627211561. The next prime is 21627211591. The reversal of 21627211564 is 46511272612.

It is not an unprimeable number, because it can be changed into a prime (21627211561) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 168922 + ... + 267934.

It is an arithmetic number, because the mean of its divisors is an integer number (935682300).

Almost surely, 2^21627211564 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21627211564, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22456375200).

21627211564 is an abundant number, since it is smaller than the sum of its proper divisors (23285538836).

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

21627211564 is a wasteful number, since it uses less digits than its factorization.

21627211564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99322 (or 99320 counting only the distinct ones).

The product of its digits is 40320, while the sum is 37.

The spelling of 21627211564 in words is "twenty-one billion, six hundred twenty-seven million, two hundred eleven thousand, five hundred sixty-four".