21201221111022 has 12 divisors (see below), whose sum is σ = 45935979073920. Its totient is φ = 7067073703668.

The previous prime is 21201221110987. The next prime is 21201221111029. The reversal of 21201221111022 is 22011112210212.

It is a Harshad number since it is a multiple of its sum of digits (18), and also a Moran number because the ratio is a prime number: 1177845617279 = 21201221111022 / (2 + 1 + 2 + 0 + 1 + 2 + 2 + 1 + 1 + 1 + 1 + 0 + 2 + 2).

It is a junction number, because it is equal to n+sod(n) for n = 21201221110986 and 21201221111004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21201221111029) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 588922808622 + ... + 588922808657.

It is an arithmetic number, because the mean of its divisors is an integer number (3827998256160).

Almost surely, 2^{21201221111022} is an apocalyptic number.

21201221111022 is an abundant number, since it is smaller than the sum of its proper divisors (24734757962898).

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

21201221111022 is a wasteful number, since it uses less digits than its factorization.

21201221111022 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1177845617287 (or 1177845617284 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 21201221111022 its reverse (22011112210212), we get a palindrome (43212333321234).

The spelling of 21201221111022 in words is "twenty-one trillion, two hundred one billion, two hundred twenty-one million, one hundred eleven thousand, twenty-two".