21942175 has 12 divisors (see below), whose sum is σ = 27873216. Its totient is φ = 17124800.

The previous prime is 21942143. The next prime is 21942191. The reversal of 21942175 is 57124912.

It is not a de Polignac number, because 21942175 - 2⁵ = 21942143 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9679 + ... + 11728.

It is an arithmetic number, because the mean of its divisors is an integer number (2322768).

Almost surely, 2^21942175 is an apocalyptic number.

21942175 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21942175 is a deficient number, since it is larger than the sum of its proper divisors (5931041).

21942175 is a wasteful number, since it uses less digits than its factorization.

21942175 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21458 (or 21453 counting only the distinct ones).

The product of its digits is 5040, while the sum is 31.

The square root of 21942175 is about 4684.2475382926. The cubic root of 21942175 is about 279.9582208072.

The spelling of 21942175 in words is "twenty-one million, nine hundred forty-two thousand, one hundred seventy-five".