221110211201021 has 2 divisors, whose sum is σ = 221110211201022. Its totient is φ = 221110211201020.

The previous prime is 221110211200973. The next prime is 221110211201023. The reversal of 221110211201021 is 120102112011122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 159511494405796 + 61598716795225 = 12629786^2 + 7848485^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221110211201021 is a prime.

It is a super-2 number, since 2×221110211201021² (a number of 29 digits) contains 22 as substring.

It is a Sophie Germain prime.

Together with 221110211201023, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221110211201023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110555105600510 + 110555105600511.

It is an arithmetic number, because the mean of its divisors is an integer number (110555105600511).

Almost surely, 2^{221110211201021} is an apocalyptic number.

It is an amenable number.

221110211201021 is a deficient number, since it is larger than the sum of its proper divisors (1).

221110211201021 is an equidigital number, since it uses as much as digits as its factorization.

221110211201021 is an evil number, because the sum of its binary digits is even.

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

Adding to 221110211201021 its reverse (120102112011122), we get a palindrome (341212323212143).

The spelling of 221110211201021 in words is "two hundred twenty-one trillion, one hundred ten billion, two hundred eleven million, two hundred one thousand, twenty-one".