205253456612021 has 2 divisors, whose sum is σ = 205253456612022. Its totient is φ = 205253456612020.

The previous prime is 205253456611993. The next prime is 205253456612033. The reversal of 205253456612021 is 120216654352502.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 148961658850225 + 56291797761796 = 12204985^2 + 7502786^2 .

It is a cyclic number.

It is not a de Polignac number, because 205253456612021 - 2³⁸ = 204978578705077 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205253456615021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102626728306010 + 102626728306011.

It is an arithmetic number, because the mean of its divisors is an integer number (102626728306011).

Almost surely, 2^{205253456612021} is an apocalyptic number.

It is an amenable number.

205253456612021 is a deficient number, since it is larger than the sum of its proper divisors (1).

205253456612021 is an equidigital number, since it uses as much as digits as its factorization.

205253456612021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864000, while the sum is 44.

The spelling of 205253456612021 in words is "two hundred five trillion, two hundred fifty-three billion, four hundred fifty-six million, six hundred twelve thousand, twenty-one".