21320335 has 4 divisors (see below), whose sum is σ = 25584408. Its totient is φ = 17056264.

The previous prime is 21320323. The next prime is 21320401. The reversal of 21320335 is 53302312.

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

It is a cyclic number.

It is not a de Polignac number, because 21320335 - 2¹¹ = 21318287 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2132029 + ... + 2132038.

It is an arithmetic number, because the mean of its divisors is an integer number (6396102).

Almost surely, 2^21320335 is an apocalyptic number.

21320335 is a deficient number, since it is larger than the sum of its proper divisors (4264073).

21320335 is an equidigital number, since it uses as much as digits as its factorization.

21320335 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4264072.

The product of its (nonzero) digits is 540, while the sum is 19.

The square root of 21320335 is about 4617.3948282554. The cubic root of 21320335 is about 277.2881699151.

Adding to 21320335 its reverse (53302312), we get a palindrome (74622647).

It can be divided in two parts, 21 and 320335, that added together give a square (320356 = 566²).

The spelling of 21320335 in words is "twenty-one million, three hundred twenty thousand, three hundred thirty-five".