21322015 has 24 divisors (see below), whose sum is σ = 30298464. Its totient is φ = 14308800.

The previous prime is 21322003. The next prime is 21322019. The reversal of 21322015 is 51022312.

It is not a de Polignac number, because 21322015 - 2⁵ = 21321983 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 21322015.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21322019) 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 23 ways as a sum of consecutive naturals, for example, 6510 + ... + 9220.

It is an arithmetic number, because the mean of its divisors is an integer number (1262436).

Almost surely, 2^21322015 is an apocalyptic number.

21322015 is a deficient number, since it is larger than the sum of its proper divisors (8976449).

21322015 is a wasteful number, since it uses less digits than its factorization.

21322015 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2751 (or 2740 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 21322015 is about 4617.5767454369. The cubic root of 21322015 is about 277.2954529759.

Adding to 21322015 its reverse (51022312), we get a palindrome (72344327).

The spelling of 21322015 in words is "twenty-one million, three hundred twenty-two thousand, fifteen".