21670323 has 8 divisors (see below), whose sum is σ = 29565888. Its totient is φ = 14110824.

The previous prime is 21670321. The next prime is 21670331. The reversal of 21670323 is 32307612.

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

It is not a de Polignac number, because 21670323 - 2¹ = 21670321 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a junction number, because it is equal to n+sod(n) for n = 21670293 and 21670302.

It is not an unprimeable number, because it can be changed into a prime (21670321) 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 7 ways as a sum of consecutive naturals, for example, 83865 + ... + 84122.

It is an arithmetic number, because the mean of its divisors is an integer number (3695736).

Almost surely, 2^21670323 is an apocalyptic number.

21670323 is a deficient number, since it is larger than the sum of its proper divisors (7895565).

21670323 is a wasteful number, since it uses less digits than its factorization.

21670323 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 168033.

The product of its (nonzero) digits is 1512, while the sum is 24.

The square root of 21670323 is about 4655.1394178907. The cubic root of 21670323 is about 278.7972345167.

Adding to 21670323 its reverse (32307612), we get a palindrome (53977935).

The spelling of 21670323 in words is "twenty-one million, six hundred seventy thousand, three hundred twenty-three".