21708674 has 8 divisors (see below), whose sum is σ = 35067900. Its totient is φ = 10019376.

The previous prime is 21708671. The next prime is 21708703. The reversal of 21708674 is 47680712.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 21687649 + 21025 = 4657^2 + 145^2 .

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

It is not an unprimeable number, because it can be changed into a prime (21708671) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 417449 + ... + 417500.

Almost surely, 2^21708674 is an apocalyptic number.

21708674 is a deficient number, since it is larger than the sum of its proper divisors (13359226).

21708674 is a wasteful number, since it uses less digits than its factorization.

21708674 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 834964.

The product of its (nonzero) digits is 18816, while the sum is 35.

The square root of 21708674 is about 4659.2568076894. The cubic root of 21708674 is about 278.9616044935.

The spelling of 21708674 in words is "twenty-one million, seven hundred eight thousand, six hundred seventy-four".