420001243 has 2 divisors, whose sum is σ = 420001244. Its totient is φ = 420001242.

The previous prime is 420001223. The next prime is 420001261. The reversal of 420001243 is 342100024.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-420001243 is a prime.

It is not a weakly prime, because it can be changed into another prime (420001223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210000621 + 210000622.

It is an arithmetic number, because the mean of its divisors is an integer number (210000622).

Almost surely, 2^420001243 is an apocalyptic number.

420001243 is a deficient number, since it is larger than the sum of its proper divisors (1).

420001243 is an equidigital number, since it uses as much as digits as its factorization.

420001243 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 192, while the sum is 16.

The square root of 420001243 is about 20493.9318579915. The cubic root of 420001243 is about 748.8879775043.

Adding to 420001243 its reverse (342100024), we get a palindrome (762101267).

The spelling of 420001243 in words is "four hundred twenty million, one thousand, two hundred forty-three".