21230075 has 6 divisors (see below), whose sum is σ = 26325324. Its totient is φ = 16984040.

The previous prime is 21230047. The next prime is 21230123. The reversal of 21230075 is 57003212.

It is not a de Polignac number, because 21230075 - 2¹⁰ = 21229051 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 424577 + ... + 424626.

It is an arithmetic number, because the mean of its divisors is an integer number (4387554).

Almost surely, 2^21230075 is an apocalyptic number.

21230075 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21230075 is a deficient number, since it is larger than the sum of its proper divisors (5095249).

21230075 is an equidigital number, since it uses as much as digits as its factorization.

21230075 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 849213 (or 849208 counting only the distinct ones).

The product of its (nonzero) digits is 420, while the sum is 20.

The square root of 21230075 is about 4607.6105521192. The cubic root of 21230075 is about 276.8963150282.

Adding to 21230075 its reverse (57003212), we get a palindrome (78233287).

The spelling of 21230075 in words is "twenty-one million, two hundred thirty thousand, seventy-five".