21116075 has 6 divisors (see below), whose sum is σ = 26183964. Its totient is φ = 16892840.

The previous prime is 21116063. The next prime is 21116099. The reversal of 21116075 is 57061112.

It is not a de Polignac number, because 21116075 - 2⁴ = 21116059 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 21116075.

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 5 ways as a sum of consecutive naturals, for example, 422297 + ... + 422346.

It is an arithmetic number, because the mean of its divisors is an integer number (4363994).

Almost surely, 2^21116075 is an apocalyptic number.

21116075 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21116075 is a deficient number, since it is larger than the sum of its proper divisors (5067889).

21116075 is an equidigital number, since it uses as much as digits as its factorization.

21116075 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 844653 (or 844648 counting only the distinct ones).

The product of its (nonzero) digits is 420, while the sum is 23.

The square root of 21116075 is about 4595.2230631385. The cubic root of 21116075 is about 276.3998047739.

Adding to 21116075 its reverse (57061112), we get a palindrome (78177187).

The spelling of 21116075 in words is "twenty-one million, one hundred sixteen thousand, seventy-five".