421062821 has 2 divisors, whose sum is σ = 421062822. Its totient is φ = 421062820.

The previous prime is 421062799. The next prime is 421062833. The reversal of 421062821 is 128260124.

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., 410265025 + 10797796 = 20255^2 + 3286^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-421062821 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (421062871) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210531410 + 210531411.

It is an arithmetic number, because the mean of its divisors is an integer number (210531411).

Almost surely, 2^421062821 is an apocalyptic number.

It is an amenable number.

421062821 is a deficient number, since it is larger than the sum of its proper divisors (1).

421062821 is an equidigital number, since it uses as much as digits as its factorization.

421062821 is an odious number, because the sum of its binary digits is odd.

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

The square root of 421062821 is about 20519.8153256797. The cubic root of 421062821 is about 749.5183995549.

The spelling of 421062821 in words is "four hundred twenty-one million, sixty-two thousand, eight hundred twenty-one".