20999075 has 6 divisors (see below), whose sum is σ = 26038884. Its totient is φ = 16799240.

The previous prime is 20999057. The next prime is 20999087. The reversal of 20999075 is 57099902.

It is not a de Polignac number, because 20999075 - 2¹⁰ = 20998051 is a prime.

It is a super-2 number, since 2×20999075² = 881922301711250, which contains 22 as substring.

It is a Duffinian 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 5 ways as a sum of consecutive naturals, for example, 419957 + ... + 420006.

It is an arithmetic number, because the mean of its divisors is an integer number (4339814).

Almost surely, 2^20999075 is an apocalyptic number.

20999075 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

20999075 is a deficient number, since it is larger than the sum of its proper divisors (5039809).

20999075 is an equidigital number, since it uses as much as digits as its factorization.

20999075 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 839973 (or 839968 counting only the distinct ones).

The product of its (nonzero) digits is 51030, while the sum is 41.

The square root of 20999075 is about 4582.4747680702. The cubic root of 20999075 is about 275.8883667773. Note that the first 3 decimals are identical.

The spelling of 20999075 in words is "twenty million, nine hundred ninety-nine thousand, seventy-five".