1210212221021 has 4 divisors (see below), whose sum is σ = 1210376905500. Its totient is φ = 1210047536544.

The previous prime is 1210212220991. The next prime is 1210212221069. The reversal of 1210212221021 is 1201222120121.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 690205377796 + 520006843225 = 830786^2 + 721115^2 .

It is a cyclic number.

It is not a de Polignac number, because 1210212221021 - 2⁶ = 1210212220957 is a prime.

It is a super-2 number, since 2×1210212221021² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1210212226021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 82331216 + ... + 82345913.

It is an arithmetic number, because the mean of its divisors is an integer number (302594226375).

Almost surely, 2^{1210212221021} is an apocalyptic number.

It is an amenable number.

1210212221021 is a deficient number, since it is larger than the sum of its proper divisors (164684479).

1210212221021 is an equidigital number, since it uses as much as digits as its factorization.

1210212221021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 164684478.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 1210212221021 its reverse (1201222120121), we get a palindrome (2411434341142).

The spelling of 1210212221021 in words is "one trillion, two hundred ten billion, two hundred twelve million, two hundred twenty-one thousand, twenty-one".