1021222111221 has 48 divisors (see below), whose sum is σ = 1617783987456. Its totient is φ = 616950373248.

The previous prime is 1021222111201. The next prime is 1021222111271. The reversal of 1021222111221 is 1221112221201.

1021222111221 is a `hidden beast` number, since 1 + 0 + 212 + 221 + 11 + 221 = 666.

It is not a de Polignac number, because 1021222111221 - 2¹⁸ = 1021221849077 is a prime.

It is a super-2 number, since 2×1021222111221² (a number of 25 digits) contains 22 as substring.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1021222111194 and 1021222111203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1021222111201) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2074516 + ... + 2519138.

It is an arithmetic number, because the mean of its divisors is an integer number (33703833072).

Almost surely, 2^{1021222111221} is an apocalyptic number.

It is an amenable number.

1021222111221 is a deficient number, since it is larger than the sum of its proper divisors (596561876235).

1021222111221 is a wasteful number, since it uses less digits than its factorization.

1021222111221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 445002 (or 444999 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 1021222111221 its reverse (1221112221201), we get a palindrome (2242334332422).

The spelling of 1021222111221 in words is "one trillion, twenty-one billion, two hundred twenty-two million, one hundred eleven thousand, two hundred twenty-one".