21021122021122 has 4 divisors (see below), whose sum is σ = 31531683031686. Its totient is φ = 10510561010560.

The previous prime is 21021122021113. The next prime is 21021122021149. The reversal of 21021122021122 is 22112022112012.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 14900302528281 + 6120819492841 = 3860091^2 + 2474029^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21021122021122.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 5255280505279 + ... + 5255280505282.

Almost surely, 2^{21021122021122} is an apocalyptic number.

21021122021122 is a deficient number, since it is larger than the sum of its proper divisors (10510561010564).

21021122021122 is a wasteful number, since it uses less digits than its factorization.

21021122021122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10510561010563.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 21021122021122 its reverse (22112022112012), we get a palindrome (43133144133134).

The spelling of 21021122021122 in words is "twenty-one trillion, twenty-one billion, one hundred twenty-two million, twenty-one thousand, one hundred twenty-two".