840459309 has 8 divisors (see below), whose sum is σ = 1130529792. Its totient is φ = 555347520.

The previous prime is 840459289. The next prime is 840459341. The reversal of 840459309 is 903954048.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 840459309 - 2²⁵ = 806904877 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (840455309) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1239277 + ... + 1239954.

It is an arithmetic number, because the mean of its divisors is an integer number (141316224).

Almost surely, 2^840459309 is an apocalyptic number.

It is an amenable number.

840459309 is a deficient number, since it is larger than the sum of its proper divisors (290070483).

840459309 is a wasteful number, since it uses less digits than its factorization.

840459309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2479347.

The product of its (nonzero) digits is 155520, while the sum is 42.

The square root of 840459309 is about 28990.6762425439. The cubic root of 840459309 is about 943.7107392758.

The spelling of 840459309 in words is "eight hundred forty million, four hundred fifty-nine thousand, three hundred nine".