202020421 has 2 divisors, whose sum is σ = 202020422. Its totient is φ = 202020420.

The previous prime is 202020359. The next prime is 202020433. The reversal of 202020421 is 124020202.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 122899396 + 79121025 = 11086^2 + 8895^2 .

It is a cyclic number.

It is not a de Polignac number, because 202020421 - 2¹¹ = 202018373 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (202020821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 101010210 + 101010211.

It is an arithmetic number, because the mean of its divisors is an integer number (101010211).

Almost surely, 2^202020421 is an apocalyptic number.

It is an amenable number.

202020421 is a deficient number, since it is larger than the sum of its proper divisors (1).

202020421 is an equidigital number, since it uses as much as digits as its factorization.

202020421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 64, while the sum is 13.

The square root of 202020421 is about 14213.3887936692. The cubic root of 202020421 is about 586.7662023709.

Adding to 202020421 its reverse (124020202), we get a palindrome (326040623).

The spelling of 202020421 in words is "two hundred two million, twenty thousand, four hundred twenty-one".