420171709 has 2 divisors, whose sum is σ = 420171710. Its totient is φ = 420171708.

The previous prime is 420171707. The next prime is 420171727. The reversal of 420171709 is 907171024.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 245799684 + 174372025 = 15678^2 + 13205^2 .

It is a cyclic number.

It is not a de Polignac number, because 420171709 - 2¹ = 420171707 is a prime.

Together with 420171707, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (420171707) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210085854 + 210085855.

It is an arithmetic number, because the mean of its divisors is an integer number (210085855).

Almost surely, 2^420171709 is an apocalyptic number.

It is an amenable number.

420171709 is a deficient number, since it is larger than the sum of its proper divisors (1).

420171709 is an equidigital number, since it uses as much as digits as its factorization.

420171709 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3528, while the sum is 31.

The square root of 420171709 is about 20498.0903744715. The cubic root of 420171709 is about 748.9892809115.

The spelling of 420171709 in words is "four hundred twenty million, one hundred seventy-one thousand, seven hundred nine".