420812621 has 2 divisors, whose sum is σ = 420812622. Its totient is φ = 420812620.

The previous prime is 420812617. The next prime is 420812641. The reversal of 420812621 is 126218024.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 249987721 + 170824900 = 15811^2 + 13070^2 .

It is a cyclic number.

It is not a de Polignac number, because 420812621 - 2² = 420812617 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (420812641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210406310 + 210406311.

It is an arithmetic number, because the mean of its divisors is an integer number (210406311).

Almost surely, 2^420812621 is an apocalyptic number.

It is an amenable number.

420812621 is a deficient number, since it is larger than the sum of its proper divisors (1).

420812621 is an equidigital number, since it uses as much as digits as its factorization.

420812621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1536, while the sum is 26.

The square root of 420812621 is about 20513.7178736571. The cubic root of 420812621 is about 749.3699128759.

The spelling of 420812621 in words is "four hundred twenty million, eight hundred twelve thousand, six hundred twenty-one".