20835009 has 16 divisors (see below), whose sum is σ = 33241600. Its totient is φ = 12821328.

The previous prime is 20834981. The next prime is 20835037. The reversal of 20835009 is 90053802.

It is an interprime number because it is at equal distance from previous prime (20834981) and next prime (20835037).

It is not a de Polignac number, because 20835009 - 2⁷ = 20834881 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20835049) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 29329 + ... + 30030.

It is an arithmetic number, because the mean of its divisors is an integer number (2077600).

Almost surely, 2^20835009 is an apocalyptic number.

It is an amenable number.

20835009 is a deficient number, since it is larger than the sum of its proper divisors (12406591).

20835009 is a wasteful number, since it uses less digits than its factorization.

20835009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59381 (or 59375 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 20835009 is about 4564.5382022719. The cubic root of 20835009 is about 275.1679811160.

The spelling of 20835009 in words is "twenty million, eight hundred thirty-five thousand, nine".