202311421021 has 2 divisors, whose sum is σ = 202311421022. Its totient is φ = 202311421020.

The previous prime is 202311420973. The next prime is 202311421027. The reversal of 202311421021 is 120124113202.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 154225071225 + 48086349796 = 392715^2 + 219286^2 .

It is a cyclic number.

It is not a de Polignac number, because 202311421021 - 2⁷ = 202311420893 is a prime.

It is a super-2 number, since 2×202311421021² (a number of 23 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 202311421021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (202311421027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 101155710510 + 101155710511.

It is an arithmetic number, because the mean of its divisors is an integer number (101155710511).

Almost surely, 2^202311421021 is an apocalyptic number.

It is an amenable number.

202311421021 is a deficient number, since it is larger than the sum of its proper divisors (1).

202311421021 is an equidigital number, since it uses as much as digits as its factorization.

202311421021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 192, while the sum is 19.

Adding to 202311421021 its reverse (120124113202), we get a palindrome (322435534223).

The spelling of 202311421021 in words is "two hundred two billion, three hundred eleven million, four hundred twenty-one thousand, twenty-one".