21682173 has 16 divisors (see below), whose sum is σ = 30804480. Its totient is φ = 13526064.

The previous prime is 21682163. The next prime is 21682187. The reversal of 21682173 is 37128612.

It is not a de Polignac number, because 21682173 - 2⁶ = 21682109 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21682173.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21682163) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 2440 + ... + 7022.

It is an arithmetic number, because the mean of its divisors is an integer number (1925280).

Almost surely, 2^21682173 is an apocalyptic number.

It is an amenable number.

21682173 is a deficient number, since it is larger than the sum of its proper divisors (9122307).

21682173 is a wasteful number, since it uses less digits than its factorization.

21682173 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4688.

The product of its digits is 4032, while the sum is 30.

The square root of 21682173 is about 4656.4120307378. The cubic root of 21682173 is about 278.8480435612.

The spelling of 21682173 in words is "twenty-one million, six hundred eighty-two thousand, one hundred seventy-three".