21113375 has 16 divisors (see below), whose sum is σ = 26753376. Its totient is φ = 16632000.

The previous prime is 21113357. The next prime is 21113399. The reversal of 21113375 is 57331112.

It is not a de Polignac number, because 21113375 - 2⁸ = 21113119 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 21113375.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7115 + ... + 9635.

It is an arithmetic number, because the mean of its divisors is an integer number (1672086).

Almost surely, 2^21113375 is an apocalyptic number.

21113375 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21113375 is a deficient number, since it is larger than the sum of its proper divisors (5640001).

21113375 is an equidigital number, since it uses as much as digits as its factorization.

21113375 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2603 (or 2593 counting only the distinct ones).

The product of its digits is 630, while the sum is 23.

The square root of 21113375 is about 4594.9292704023. The cubic root of 21113375 is about 276.3880236817.

Adding to 21113375 its reverse (57331112), we get a palindrome (78444487).

The spelling of 21113375 in words is "twenty-one million, one hundred thirteen thousand, three hundred seventy-five".