20835409 has 8 divisors (see below), whose sum is σ = 23846400. Its totient is φ = 17833056.

The previous prime is 20835389. The next prime is 20835431. The reversal of 20835409 is 90453802.

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 20835409 - 2¹⁵ = 20802641 is a prime.

It is a super-2 number, since 2×20835409² = 868228536394562, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20835469) 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, 4317 + ... + 7765.

It is an arithmetic number, because the mean of its divisors is an integer number (2980800).

Almost surely, 2^20835409 is an apocalyptic number.

It is an amenable number.

20835409 is a deficient number, since it is larger than the sum of its proper divisors (3010991).

20835409 is an equidigital number, since it uses as much as digits as its factorization.

20835409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4319.

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 20835409 is about 4564.5820181042. The cubic root of 20835409 is about 275.1697420382.

The spelling of 20835409 in words is "twenty million, eight hundred thirty-five thousand, four hundred nine".