21634075 has 6 divisors (see below), whose sum is σ = 26826284. Its totient is φ = 17307240.

The previous prime is 21634073. The next prime is 21634079. The reversal of 21634075 is 57043612.

It is not a de Polignac number, because 21634075 - 2¹ = 21634073 is a prime.

It is a super-2 number, since 2×21634075² = 936066402211250, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21634073) by changing a digit.

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, 432657 + ... + 432706.

Almost surely, 2^21634075 is an apocalyptic number.

21634075 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21634075 is a deficient number, since it is larger than the sum of its proper divisors (5192209).

21634075 is an equidigital number, since it uses as much as digits as its factorization.

21634075 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 865373 (or 865368 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 28.

The square root of 21634075 is about 4651.2444571319. The cubic root of 21634075 is about 278.6416995010.

Adding to 21634075 its reverse (57043612), we get a palindrome (78677687).

The spelling of 21634075 in words is "twenty-one million, six hundred thirty-four thousand, seventy-five".