421666051 has 2 divisors, whose sum is σ = 421666052. Its totient is φ = 421666050.

The previous prime is 421666019. The next prime is 421666057. The reversal of 421666051 is 150666124.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 421666051 - 2⁵ = 421666019 is a prime.

It is a Chen prime.

It is equal to p_22428445 and since 421666051 and 22428445 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (421666057) 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, 210833025 + 210833026.

It is an arithmetic number, because the mean of its divisors is an integer number (210833026).

Almost surely, 2^421666051 is an apocalyptic number.

421666051 is a deficient number, since it is larger than the sum of its proper divisors (1).

421666051 is an equidigital number, since it uses as much as digits as its factorization.

421666051 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 421666051 is about 20534.5087839958. The cubic root of 421666051 is about 749.8761579223.

The spelling of 421666051 in words is "four hundred twenty-one million, six hundred sixty-six thousand, fifty-one".