222121201222221 has 12 divisors (see below), whose sum is σ = 344514516181632. Its totient is φ = 126926400698328.

The previous prime is 222121201222211. The next prime is 222121201222313. The reversal of 222121201222221 is 122222102121222.

It is a happy number.

It is not a de Polignac number, because 222121201222221 - 2⁶ = 222121201222157 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 222121201222191 and 222121201222200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (222121201222211) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 755514289725 + ... + 755514290018.

It is an arithmetic number, because the mean of its divisors is an integer number (28709543015136).

Almost surely, 2^{222121201222221} is an apocalyptic number.

222121201222221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

222121201222221 is a deficient number, since it is larger than the sum of its proper divisors (122393314959411).

222121201222221 is a wasteful number, since it uses less digits than its factorization.

222121201222221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1511028579760 (or 1511028579753 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 24.

Adding to 222121201222221 its reverse (122222102121222), we get a palindrome (344343303343443).

The spelling of 222121201222221 in words is "two hundred twenty-two trillion, one hundred twenty-one billion, two hundred one million, two hundred twenty-two thousand, two hundred twenty-one".