21021111212222 has 32 divisors (see below), whose sum is σ = 34504697092320. Its totient is φ = 9525470330880.

The previous prime is 21021111212191. The next prime is 21021111212239. The reversal of 21021111212222 is 22221211112012.

It is a junction number, because it is equal to n+sod(n) for n = 21021111212194 and 21021111212203.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 58666304 + ... + 59023532.

It is an arithmetic number, because the mean of its divisors is an integer number (1078271784135).

Almost surely, 2^{21021111212222} is an apocalyptic number.

21021111212222 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21021111212222 is a deficient number, since it is larger than the sum of its proper divisors (13483585880098).

21021111212222 is a wasteful number, since it uses less digits than its factorization.

21021111212222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 365516.

The product of its (nonzero) digits is 128, while the sum is 20.

Adding to 21021111212222 its reverse (22221211112012), we get a palindrome (43242322324234).

The spelling of 21021111212222 in words is "twenty-one trillion, twenty-one billion, one hundred eleven million, two hundred twelve thousand, two hundred twenty-two".