421591309 has 16 divisors (see below), whose sum is σ = 438177600. Its totient is φ = 405415296.

The previous prime is 421591273. The next prime is 421591319. The reversal of 421591309 is 903195124.

It is a cyclic number.

It is not a de Polignac number, because 421591309 - 2¹⁹ = 421067021 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (421591319) 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 in 15 ways as a sum of consecutive naturals, for example, 655342 + ... + 655984.

It is an arithmetic number, because the mean of its divisors is an integer number (27386100).

Almost surely, 2^421591309 is an apocalyptic number.

It is an amenable number.

421591309 is a deficient number, since it is larger than the sum of its proper divisors (16586291).

421591309 is a wasteful number, since it uses less digits than its factorization.

421591309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 924.

The product of its (nonzero) digits is 9720, while the sum is 34.

The square root of 421591309 is about 20532.6887912908. The cubic root of 421591309 is about 749.8318491180.

The spelling of 421591309 in words is "four hundred twenty-one million, five hundred ninety-one thousand, three hundred nine".