420221999 has 2 divisors, whose sum is σ = 420222000. Its totient is φ = 420221998.

The previous prime is 420221981. The next prime is 420222007. The reversal of 420221999 is 999122024.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-420221999 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (420221959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210110999 + 210111000.

It is an arithmetic number, because the mean of its divisors is an integer number (210111000).

Almost surely, 2^420221999 is an apocalyptic number.

420221999 is a deficient number, since it is larger than the sum of its proper divisors (1).

420221999 is an equidigital number, since it uses as much as digits as its factorization.

420221999 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23328, while the sum is 38.

The square root of 420221999 is about 20499.3170374040. The cubic root of 420221999 is about 749.0191616860.

The spelling of 420221999 in words is "four hundred twenty million, two hundred twenty-one thousand, nine hundred ninety-nine".