21564082212 has 24 divisors (see below), whose sum is σ = 51486337056. Its totient is φ = 7020863808.

The previous prime is 21564082171. The next prime is 21564082213. The reversal of 21564082212 is 21228046512.

It is a super-3 number, since 3×21564082212³ (a number of 32 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (21564082213) 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, 20894913 + ... + 20895944.

It is an arithmetic number, because the mean of its divisors is an integer number (2145264044).

Almost surely, 2^21564082212 is an apocalyptic number.

It is an amenable number.

21564082212 is an abundant number, since it is smaller than the sum of its proper divisors (29922254844).

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

21564082212 is a wasteful number, since it uses less digits than its factorization.

21564082212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41790907 (or 41790905 counting only the distinct ones).

The product of its (nonzero) digits is 15360, while the sum is 33.

The spelling of 21564082212 in words is "twenty-one billion, five hundred sixty-four million, eighty-two thousand, two hundred twelve".