20835121 has 4 divisors (see below), whose sum is σ = 20849652. Its totient is φ = 20820592.

The previous prime is 20835103. The next prime is 20835151. The reversal of 20835121 is 12153802.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 12215025 + 8620096 = 3495^2 + 2936^2 .

It is a cyclic number.

It is not a de Polignac number, because 20835121 - 2⁹ = 20834609 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20835092 and 20835101.

It is not an unprimeable number, because it can be changed into a prime (20835151) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4846 + ... + 8071.

It is an arithmetic number, because the mean of its divisors is an integer number (5212413).

Almost surely, 2^20835121 is an apocalyptic number.

It is an amenable number.

20835121 is a deficient number, since it is larger than the sum of its proper divisors (14531).

20835121 is a wasteful number, since it uses less digits than its factorization.

20835121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14530.

The product of its (nonzero) digits is 480, while the sum is 22.

The square root of 20835121 is about 4564.5504707474. The cubic root of 20835121 is about 275.1684741765.

Adding to 20835121 its reverse (12153802), we get a palindrome (32988923).

The spelling of 20835121 in words is "twenty million, eight hundred thirty-five thousand, one hundred twenty-one".