21317234 has 8 divisors (see below), whose sum is σ = 32061360. Its totient is φ = 10630116.

The previous prime is 21317213. The next prime is 21317249. The reversal of 21317234 is 43271312.

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

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13304 + ... + 14819.

It is an arithmetic number, because the mean of its divisors is an integer number (4007670).

Almost surely, 2^21317234 is an apocalyptic number.

21317234 is a deficient number, since it is larger than the sum of its proper divisors (10744126).

21317234 is a wasteful number, since it uses less digits than its factorization.

21317234 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28504.

The product of its digits is 1008, while the sum is 23.

The square root of 21317234 is about 4617.0590206321. The cubic root of 21317234 is about 277.2747255937.

Adding to 21317234 its reverse (43271312), we get a palindrome (64588546).

The spelling of 21317234 in words is "twenty-one million, three hundred seventeen thousand, two hundred thirty-four".