20846989 has 4 divisors (see below), whose sum is σ = 20858656. Its totient is φ = 20835324.

The previous prime is 20846977. The next prime is 20847007. The reversal of 20846989 is 98964802.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 20846989 - 2⁵ = 20846957 is a prime.

It is a super-2 number, since 2×20846989² = 869193900732242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20856989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2529 + ... + 6934.

It is an arithmetic number, because the mean of its divisors is an integer number (5214664).

Almost surely, 2^20846989 is an apocalyptic number.

It is an amenable number.

20846989 is a deficient number, since it is larger than the sum of its proper divisors (11667).

20846989 is an equidigital number, since it uses as much as digits as its factorization.

20846989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11666.

The product of its (nonzero) digits is 248832, while the sum is 46.

The square root of 20846989 is about 4565.8503041602. The cubic root of 20846989 is about 275.2207109675.

The spelling of 20846989 in words is "twenty million, eight hundred forty-six thousand, nine hundred eighty-nine".