21230746 has 8 divisors (see below), whose sum is σ = 32523840. Its totient is φ = 10389468.

The previous prime is 21230719. The next prime is 21230749. The reversal of 21230746 is 64703212.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21230746.

It is not an unprimeable number, because it can be changed into a prime (21230749) 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, 112836 + ... + 113023.

It is an arithmetic number, because the mean of its divisors is an integer number (4065480).

Almost surely, 2^21230746 is an apocalyptic number.

21230746 is a deficient number, since it is larger than the sum of its proper divisors (11293094).

21230746 is a wasteful number, since it uses less digits than its factorization.

21230746 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 225908.

The product of its (nonzero) digits is 2016, while the sum is 25.

The square root of 21230746 is about 4607.6833658575. The cubic root of 21230746 is about 276.8992322022.

Adding to 21230746 its reverse (64703212), we get a palindrome (85933958).

The spelling of 21230746 in words is "twenty-one million, two hundred thirty thousand, seven hundred forty-six".