21722521212 has 72 divisors (see below), whose sum is σ = 65482400256. Its totient is φ = 5936588064.

The previous prime is 21722521211. The next prime is 21722521237. The reversal of 21722521212 is 21212522712.

21722521212 is a `hidden beast` number, since 217 + 225 + 212 + 12 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21722521211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1868128 + ... + 1879719.

Almost surely, 2^21722521212 is an apocalyptic number.

It is an amenable number.

21722521212 is an abundant number, since it is smaller than the sum of its proper divisors (43759879044).

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

21722521212 is a wasteful number, since it uses less digits than its factorization.

21722521212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3747887 (or 3747882 counting only the distinct ones).

The product of its digits is 2240, while the sum is 27.

The spelling of 21722521212 in words is "twenty-one billion, seven hundred twenty-two million, five hundred twenty-one thousand, two hundred twelve".