21175105 has 16 divisors (see below), whose sum is σ = 29635200. Its totient is φ = 14518896.

The previous prime is 21175097. The next prime is 21175117. The reversal of 21175105 is 50157112.

It is not a de Polignac number, because 21175105 - 2³ = 21175097 is a prime.

It is a super-2 number, since 2×21175105² = 896770143522050, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4459 + ... + 7888.

It is an arithmetic number, because the mean of its divisors is an integer number (1852200).

Almost surely, 2^21175105 is an apocalyptic number.

It is an amenable number.

21175105 is a deficient number, since it is larger than the sum of its proper divisors (8460095).

21175105 is an equidigital number, since it uses as much as digits as its factorization.

21175105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12373 (or 12359 counting only the distinct ones).

The product of its (nonzero) digits is 350, while the sum is 22.

The square root of 21175105 is about 4601.6415549236. The cubic root of 21175105 is about 276.6571237495.

The spelling of 21175105 in words is "twenty-one million, one hundred seventy-five thousand, one hundred five".