21096689 has 4 divisors (see below), whose sum is σ = 21454320. Its totient is φ = 20739060.

The previous prime is 21096683. The next prime is 21096739. The reversal of 21096689 is 98669012.

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.

It is a cyclic number.

It is not a de Polignac number, because 21096689 - 2²⁰ = 20048113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21096683) 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, 178727 + ... + 178844.

It is an arithmetic number, because the mean of its divisors is an integer number (5363580).

Almost surely, 2^21096689 is an apocalyptic number.

It is an amenable number.

21096689 is a deficient number, since it is larger than the sum of its proper divisors (357631).

21096689 is an equidigital number, since it uses as much as digits as its factorization.

21096689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 357630.

The product of its (nonzero) digits is 46656, while the sum is 41.

The square root of 21096689 is about 4593.1132143678. The cubic root of 21096689 is about 276.3151942389.

The spelling of 21096689 in words is "twenty-one million, ninety-six thousand, six hundred eighty-nine".