21113413 has 4 divisors (see below), whose sum is σ = 21138208. Its totient is φ = 21088620.

The previous prime is 21113399. The next prime is 21113423. The reversal of 21113413 is 31431112.

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 21113413 - 2¹³ = 21105221 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 (21113423) 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, 11073 + ... + 12838.

It is an arithmetic number, because the mean of its divisors is an integer number (5284552).

Almost surely, 2^21113413 is an apocalyptic number.

It is an amenable number.

21113413 is a deficient number, since it is larger than the sum of its proper divisors (24795).

21113413 is an equidigital number, since it uses as much as digits as its factorization.

21113413 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24794.

The product of its digits is 72, while the sum is 16.

The square root of 21113413 is about 4594.9334053934. The cubic root of 21113413 is about 276.3881894966.

Adding to 21113413 its reverse (31431112), we get a palindrome (52544525).

The spelling of 21113413 in words is "twenty-one million, one hundred thirteen thousand, four hundred thirteen".