21550323 has 8 divisors (see below), whose sum is σ = 28838608. Its totient is φ = 14314464.

The previous prime is 21550289. The next prime is 21550327. The reversal of 21550323 is 32305512.

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

It is not a de Polignac number, because 21550323 - 2⁶ = 21550259 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21550323.

It is not an unprimeable number, because it can be changed into a prime (21550327) 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, 12136 + ... + 13797.

It is an arithmetic number, because the mean of its divisors is an integer number (3604826).

Almost surely, 2^21550323 is an apocalyptic number.

21550323 is a deficient number, since it is larger than the sum of its proper divisors (7288285).

21550323 is a wasteful number, since it uses less digits than its factorization.

21550323 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26213.

The product of its (nonzero) digits is 900, while the sum is 21.

The square root of 21550323 is about 4642.2325448000. The cubic root of 21550323 is about 278.2816659407.

Adding to 21550323 its reverse (32305512), we get a palindrome (53855835).

The spelling of 21550323 in words is "twenty-one million, five hundred fifty thousand, three hundred twenty-three".