21674605 has 8 divisors (see below), whose sum is σ = 26208864. Its totient is φ = 17206800.

The previous prime is 21674591. The next prime is 21674617. The reversal of 21674605 is 50647612.

21674605 = 340² + 341² + ... + 470².

It is a happy number.

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

It is a de Polignac number, because none of the positive numbers 2^k-21674605 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15891 + ... + 17200.

It is an arithmetic number, because the mean of its divisors is an integer number (3276108).

Almost surely, 2^21674605 is an apocalyptic number.

It is an amenable number.

21674605 is a deficient number, since it is larger than the sum of its proper divisors (4534259).

21674605 is a wasteful number, since it uses less digits than its factorization.

21674605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33227.

The product of its (nonzero) digits is 10080, while the sum is 31.

The square root of 21674605 is about 4655.5993169516. The cubic root of 21674605 is about 278.8155965125.

The spelling of 21674605 in words is "twenty-one million, six hundred seventy-four thousand, six hundred five".