840509189 has 8 divisors (see below), whose sum is σ = 958408920. Its totient is φ = 730215936.

The previous prime is 840509183. The next prime is 840509209. The reversal of 840509189 is 981905048.

It can be written as a sum of positive squares in 4 ways, for example, as 2696164 + 837813025 = 1642^2 + 28945^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 840509189 - 2²⁰ = 839460613 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 (840509183) 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, 1901384 + ... + 1901825.

It is an arithmetic number, because the mean of its divisors is an integer number (119801115).

Almost surely, 2^840509189 is an apocalyptic number.

It is an amenable number.

840509189 is a deficient number, since it is larger than the sum of its proper divisors (117899731).

840509189 is a wasteful number, since it uses less digits than its factorization.

840509189 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3803239.

The product of its (nonzero) digits is 103680, while the sum is 44.

The square root of 840509189 is about 28991.5365063668. The cubic root of 840509189 is about 943.7294081790.

It can be divided in two parts, 84050 and 9189, that added together give a palindrome (93239).

The spelling of 840509189 in words is "eight hundred forty million, five hundred nine thousand, one hundred eighty-nine".