22021212021 has 16 divisors (see below), whose sum is σ = 32725022400. Its totient is φ = 13090007808.

The previous prime is 22021212011. The next prime is 22021212113. The reversal of 22021212021 is 12021212022.

It is not a de Polignac number, because 22021212021 - 2¹³ = 22021203829 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22021212011) 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, 11361886 + ... + 11363823.

It is an arithmetic number, because the mean of its divisors is an integer number (2045313900).

Almost surely, 2^22021212021 is an apocalyptic number.

It is an amenable number.

22021212021 is a deficient number, since it is larger than the sum of its proper divisors (10703810379).

22021212021 is a wasteful number, since it uses less digits than its factorization.

22021212021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22725748.

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 22021212021 its reverse (12021212022), we get a palindrome (34042424043).

Subtracting from 22021212021 its reverse (12021212022), we obtain a palindrome (9999999999).

The spelling of 22021212021 in words is "twenty-two billion, twenty-one million, two hundred twelve thousand, twenty-one".