421257251 has 2 divisors, whose sum is σ = 421257252. Its totient is φ = 421257250.

The previous prime is 421257241. The next prime is 421257301. The reversal of 421257251 is 152752124.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-421257251 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (421257211) 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, 210628625 + 210628626.

It is an arithmetic number, because the mean of its divisors is an integer number (210628626).

Almost surely, 2^421257251 is an apocalyptic number.

421257251 is a deficient number, since it is larger than the sum of its proper divisors (1).

421257251 is an equidigital number, since it uses as much as digits as its factorization.

421257251 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5600, while the sum is 29.

The square root of 421257251 is about 20524.5523946321. The cubic root of 421257251 is about 749.6337476933.

The spelling of 421257251 in words is "four hundred twenty-one million, two hundred fifty-seven thousand, two hundred fifty-one".