21221212210022 has 16 divisors (see below), whose sum is σ = 34726463644752. Its totient is φ = 9645771198720.

The previous prime is 21221212209997. The next prime is 21221212210043. The reversal of 21221212210022 is 22001221212212.

It is a junction number, because it is equal to n+sod(n) for n = 21221212209976 and 21221212210003.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10789823 + ... + 12604074.

It is an arithmetic number, because the mean of its divisors is an integer number (2170403977797).

Almost surely, 2^{21221212210022} is an apocalyptic number.

21221212210022 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21221212210022 is a deficient number, since it is larger than the sum of its proper divisors (13505251434730).

21221212210022 is a wasteful number, since it uses less digits than its factorization.

21221212210022 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23435143.

The product of its (nonzero) digits is 256, while the sum is 20.

Adding to 21221212210022 its reverse (22001221212212), we get a palindrome (43222433422234).

The spelling of 21221212210022 in words is "twenty-one trillion, two hundred twenty-one billion, two hundred twelve million, two hundred ten thousand, twenty-two".