420444491 has 2 divisors, whose sum is σ = 420444492. Its totient is φ = 420444490.

The previous prime is 420444473. The next prime is 420444499. The reversal of 420444491 is 194444024.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-420444491 is a prime.

It is not a weakly prime, because it can be changed into another prime (420444499) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210222245 + 210222246.

It is an arithmetic number, because the mean of its divisors is an integer number (210222246).

Almost surely, 2^420444491 is an apocalyptic number.

420444491 is a deficient number, since it is larger than the sum of its proper divisors (1).

420444491 is an equidigital number, since it uses as much as digits as its factorization.

420444491 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18432, while the sum is 32.

The square root of 420444491 is about 20504.7431342117. The cubic root of 420444491 is about 749.1513310064.

The spelling of 420444491 in words is "four hundred twenty million, four hundred forty-four thousand, four hundred ninety-one".