21222220123 has 6 divisors (see below), whose sum is σ = 22980274044. Its totient is φ = 19589741496.

The previous prime is 21222220109. The next prime is 21222220127. The reversal of 21222220123 is 32102222212.

It is not a de Polignac number, because 21222220123 - 2²¹ = 21220122971 is a prime.

It is a super-2 number, since 2×21222220123² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21222220123.

It is not an unprimeable number, because it can be changed into a prime (21222220127) 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, 62787465 + ... + 62787802.

It is an arithmetic number, because the mean of its divisors is an integer number (3830045674).

Almost surely, 2^21222220123 is an apocalyptic number.

21222220123 is a deficient number, since it is larger than the sum of its proper divisors (1758053921).

21222220123 is a wasteful number, since it uses less digits than its factorization.

21222220123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125575293 (or 125575280 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 19.

Adding to 21222220123 its reverse (32102222212), we get a palindrome (53324442335).

The spelling of 21222220123 in words is "twenty-one billion, two hundred twenty-two million, two hundred twenty thousand, one hundred twenty-three".