21104275 has 12 divisors (see below), whose sum is σ = 26261712. Its totient is φ = 16823840.

The previous prime is 21104267. The next prime is 21104287. The reversal of 21104275 is 57240112.

It is a happy number.

It is not a de Polignac number, because 21104275 - 2³ = 21104267 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6594 + ... + 9256.

It is an arithmetic number, because the mean of its divisors is an integer number (2188476).

Almost surely, 2^21104275 is an apocalyptic number.

21104275 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21104275 is a deficient number, since it is larger than the sum of its proper divisors (5157437).

21104275 is a wasteful number, since it uses less digits than its factorization.

21104275 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2990 (or 2985 counting only the distinct ones).

The product of its (nonzero) digits is 560, while the sum is 22.

The square root of 21104275 is about 4593.9389416926. The cubic root of 21104275 is about 276.3483096387.

Adding to 21104275 its reverse (57240112), we get a palindrome (78344387).

The spelling of 21104275 in words is "twenty-one million, one hundred four thousand, two hundred seventy-five".