211331201021 has 2 divisors, whose sum is σ = 211331201022. Its totient is φ = 211331201020.

The previous prime is 211331200979. The next prime is 211331201069. The reversal of 211331201021 is 120102133112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 138923925625 + 72407275396 = 372725^2 + 269086^2 .

It is a cyclic number.

It is not a de Polignac number, because 211331201021 - 2¹⁰ = 211331199997 is a prime.

It is a super-2 number, since 2×211331201021² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (211331201821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105665600510 + 105665600511.

It is an arithmetic number, because the mean of its divisors is an integer number (105665600511).

Almost surely, 2^211331201021 is an apocalyptic number.

It is an amenable number.

211331201021 is a deficient number, since it is larger than the sum of its proper divisors (1).

211331201021 is an equidigital number, since it uses as much as digits as its factorization.

211331201021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 211331201021 its reverse (120102133112), we get a palindrome (331433334133).

The spelling of 211331201021 in words is "two hundred eleven billion, three hundred thirty-one million, two hundred one thousand, twenty-one".