21562201212 has 12 divisors (see below), whose sum is σ = 50311802856. Its totient is φ = 7187400400.

The previous prime is 21562201211. The next prime is 21562201223. The reversal of 21562201212 is 21210226512.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×21562201212² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21562201211) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 898425039 + ... + 898425062.

It is an arithmetic number, because the mean of its divisors is an integer number (4192650238).

Almost surely, 2^21562201212 is an apocalyptic number.

It is an amenable number.

21562201212 is an abundant number, since it is smaller than the sum of its proper divisors (28749601644).

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

21562201212 is a wasteful number, since it uses less digits than its factorization.

21562201212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1796850108 (or 1796850106 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 24.

Adding to 21562201212 its reverse (21210226512), we get a palindrome (42772427724).

The spelling of 21562201212 in words is "twenty-one billion, five hundred sixty-two million, two hundred one thousand, two hundred twelve".