21722313 has 8 divisors (see below), whose sum is σ = 28990528. Its totient is φ = 14467824.

The previous prime is 21722297. The next prime is 21722317. The reversal of 21722313 is 31322712.

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

It is not a de Polignac number, because 21722313 - 2⁴ = 21722297 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 21722313.

It is not an unprimeable number, because it can be changed into a prime (21722317) 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, 1131 + ... + 6687.

It is an arithmetic number, because the mean of its divisors is an integer number (3623816).

Almost surely, 2^21722313 is an apocalyptic number.

It is an amenable number.

21722313 is a deficient number, since it is larger than the sum of its proper divisors (7268215).

21722313 is a wasteful number, since it uses less digits than its factorization.

21722313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6863.

The product of its digits is 504, while the sum is 21.

The square root of 21722313 is about 4660.7202233131. The cubic root of 21722313 is about 279.0200137234.

The spelling of 21722313 in words is "twenty-one million, seven hundred twenty-two thousand, three hundred thirteen".