21353389 has 8 divisors (see below), whose sum is σ = 22095360. Its totient is φ = 20614800.

The previous prime is 21353383. The next prime is 21353401. The reversal of 21353389 is 98335312.

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 21353389 - 2⁵ = 21353357 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21353383) 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, 25032 + ... + 25870.

It is an arithmetic number, because the mean of its divisors is an integer number (2761920).

Almost surely, 2^21353389 is an apocalyptic number.

It is an amenable number.

21353389 is a deficient number, since it is larger than the sum of its proper divisors (741971).

21353389 is an equidigital number, since it uses as much as digits as its factorization.

21353389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1691.

The product of its digits is 19440, while the sum is 34.

The square root of 21353389 is about 4620.9727330942. The cubic root of 21353389 is about 277.4313939103.

The spelling of 21353389 in words is "twenty-one million, three hundred fifty-three thousand, three hundred eighty-nine".