21317606 has 8 divisors (see below), whose sum is σ = 32414664. Its totient is φ = 10512720.

The previous prime is 21317539. The next prime is 21317623. The reversal of 21317606 is 60671312.

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

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

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, 72860 + ... + 73151.

It is an arithmetic number, because the mean of its divisors is an integer number (4051833).

Almost surely, 2^21317606 is an apocalyptic number.

21317606 is a deficient number, since it is larger than the sum of its proper divisors (11097058).

21317606 is a wasteful number, since it uses less digits than its factorization.

21317606 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146086.

The product of its (nonzero) digits is 1512, while the sum is 26.

The square root of 21317606 is about 4617.0993058413. The cubic root of 21317606 is about 277.2763384609.

Adding to 21317606 its reverse (60671312), we get a palindrome (81988918).

The spelling of 21317606 in words is "twenty-one million, three hundred seventeen thousand, six hundred six".