10121210211221 has 2 divisors, whose sum is σ = 10121210211222. Its totient is φ = 10121210211220.

The previous prime is 10121210211209. The next prime is 10121210211241. The reversal of 10121210211221 is 12211201212101.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6525214802500 + 3595995408721 = 2554450^2 + 1896311^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-10121210211221 is a prime.

It is a super-2 number, since 2×10121210211221² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 10121210211221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (10121210211241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5060605105610 + 5060605105611.

It is an arithmetic number, because the mean of its divisors is an integer number (5060605105611).

Almost surely, 2^{10121210211221} is an apocalyptic number.

It is an amenable number.

10121210211221 is a deficient number, since it is larger than the sum of its proper divisors (1).

10121210211221 is an equidigital number, since it uses as much as digits as its factorization.

10121210211221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 10121210211221 its reverse (12211201212101), we get a palindrome (22332411423322).

The spelling of 10121210211221 in words is "ten trillion, one hundred twenty-one billion, two hundred ten million, two hundred eleven thousand, two hundred twenty-one".