21222315 has 12 divisors (see below), whose sum is σ = 36785424. Its totient is φ = 11318544.

The previous prime is 21222293. The next prime is 21222343. The reversal of 21222315 is 51322212.

It is not a de Polignac number, because 21222315 - 2⁶ = 21222251 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 235759 + ... + 235848.

It is an arithmetic number, because the mean of its divisors is an integer number (3065452).

Almost surely, 2^21222315 is an apocalyptic number.

21222315 is a deficient number, since it is larger than the sum of its proper divisors (15563109).

21222315 is a wasteful number, since it uses less digits than its factorization.

21222315 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 471618 (or 471615 counting only the distinct ones).

The product of its digits is 240, while the sum is 18.

The square root of 21222315 is about 4606.7683900973. The cubic root of 21222315 is about 276.8625739438.

Adding to 21222315 its reverse (51322212), we get a palindrome (72544527).

The spelling of 21222315 in words is "twenty-one million, two hundred twenty-two thousand, three hundred fifteen".