21675445 has 8 divisors (see below), whose sum is σ = 28375200. Its totient is φ = 15763920.

The previous prime is 21675427. The next prime is 21675449. The reversal of 21675445 is 54457612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21675445 - 2¹³ = 21667253 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21675445.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21675449) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 196995 + ... + 197104.

It is an arithmetic number, because the mean of its divisors is an integer number (3546900).

Almost surely, 2^21675445 is an apocalyptic number.

It is an amenable number.

21675445 is a deficient number, since it is larger than the sum of its proper divisors (6699755).

21675445 is a wasteful number, since it uses less digits than its factorization.

21675445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 394115.

The product of its digits is 33600, while the sum is 34.

The square root of 21675445 is about 4655.6895300267. The cubic root of 21675445 is about 278.8191983017.

The spelling of 21675445 in words is "twenty-one million, six hundred seventy-five thousand, four hundred forty-five".