21674447 has 4 divisors (see below), whose sum is σ = 21693696. Its totient is φ = 21655200.

The previous prime is 21674431. The next prime is 21674449. The reversal of 21674447 is 74447612.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21674447 - 2⁴ = 21674431 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21674449) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7823 + ... + 10224.

It is an arithmetic number, because the mean of its divisors is an integer number (5423424).

Almost surely, 2^21674447 is an apocalyptic number.

21674447 is a deficient number, since it is larger than the sum of its proper divisors (19249).

21674447 is a wasteful number, since it uses less digits than its factorization.

21674447 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19248.

The product of its digits is 37632, while the sum is 35.

The square root of 21674447 is about 4655.5823481064. The cubic root of 21674447 is about 278.8149190227.

The spelling of 21674447 in words is "twenty-one million, six hundred seventy-four thousand, four hundred forty-seven".