21211201212222 has 32 divisors (see below), whose sum is σ = 51334671843072. Its totient is φ = 5703852426624.

The previous prime is 21211201212221. The next prime is 21211201212247. The reversal of 21211201212222 is 22221210211212.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21211201212221) 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, 14853781648 + ... + 14853783075.

It is an arithmetic number, because the mean of its divisors is an integer number (1604208495096).

Almost surely, 2^{21211201212222} is an apocalyptic number.

21211201212222 is an abundant number, since it is smaller than the sum of its proper divisors (30123470630850).

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

21211201212222 is a wasteful number, since it uses less digits than its factorization.

21211201212222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29707564752.

The product of its (nonzero) digits is 256, while the sum is 21.

Adding to 21211201212222 its reverse (22221210211212), we get a palindrome (43432411423434).

The spelling of 21211201212222 in words is "twenty-one trillion, two hundred eleven billion, two hundred one million, two hundred twelve thousand, two hundred twenty-two".