21212022072 has 32 divisors (see below), whose sum is σ = 54323473680. Its totient is φ = 6898218240.

The previous prime is 21212022071. The next prime is 21212022127. The reversal of 21212022072 is 27022021212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21212022071) 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, 10777483 + ... + 10779450.

Almost surely, 2^21212022072 is an apocalyptic number.

It is an amenable number.

21212022072 is an abundant number, since it is smaller than the sum of its proper divisors (33111451608).

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

21212022072 is a wasteful number, since it uses less digits than its factorization.

21212022072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21556983 (or 21556979 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 21.

Adding to 21212022072 its reverse (27022021212), we get a palindrome (48234043284).

The spelling of 21212022072 in words is "twenty-one billion, two hundred twelve million, twenty-two thousand, seventy-two".