420638593 has 2 divisors, whose sum is σ = 420638594. Its totient is φ = 420638592.

The previous prime is 420638573. The next prime is 420638623. The reversal of 420638593 is 395836024.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 346816129 + 73822464 = 18623^2 + 8592^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-420638593 is a prime.

It is not a weakly prime, because it can be changed into another prime (420638503) 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, 210319296 + 210319297.

It is an arithmetic number, because the mean of its divisors is an integer number (210319297).

Almost surely, 2^420638593 is an apocalyptic number.

It is an amenable number.

420638593 is a deficient number, since it is larger than the sum of its proper divisors (1).

420638593 is an equidigital number, since it uses as much as digits as its factorization.

420638593 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 155520, while the sum is 40.

The square root of 420638593 is about 20509.4756880814. The cubic root of 420638593 is about 749.2665974317.

The spelling of 420638593 in words is "four hundred twenty million, six hundred thirty-eight thousand, five hundred ninety-three".