21036335 has 4 divisors (see below), whose sum is σ = 25243608. Its totient is φ = 16829064.

The previous prime is 21036311. The next prime is 21036341. The reversal of 21036335 is 53363012.

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 21036335 - 2⁶ = 21036271 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21036335.

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, 2103629 + ... + 2103638.

It is an arithmetic number, because the mean of its divisors is an integer number (6310902).

Almost surely, 2^21036335 is an apocalyptic number.

21036335 is a deficient number, since it is larger than the sum of its proper divisors (4207273).

21036335 is an equidigital number, since it uses as much as digits as its factorization.

21036335 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4207272.

The product of its (nonzero) digits is 1620, while the sum is 23.

The square root of 21036335 is about 4586.5384550879. The cubic root of 21036335 is about 276.0514458115.

Adding to 21036335 its reverse (53363012), we get a palindrome (74399347).

The spelling of 21036335 in words is "twenty-one million, thirty-six thousand, three hundred thirty-five".