21223310 has 32 divisors (see below), whose sum is σ = 40800672. Its totient is φ = 7920640.

The previous prime is 21223297. The next prime is 21223333. The reversal of 21223310 is 1332212.

It is a happy number.

It is a super-2 number, since 2×21223310² = 900857774712200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21794 + ... + 22746.

It is an arithmetic number, because the mean of its divisors is an integer number (1275021).

Almost surely, 2^21223310 is an apocalyptic number.

21223310 is a deficient number, since it is larger than the sum of its proper divisors (19577362).

21223310 is a wasteful number, since it uses less digits than its factorization.

21223310 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1108.

The product of its (nonzero) digits is 72, while the sum is 14.

The square root of 21223310 is about 4606.8763821053. The cubic root of 21223310 is about 276.8669007409.

Adding to 21223310 its reverse (1332212), we get a palindrome (22555522).

The spelling of 21223310 in words is "twenty-one million, two hundred twenty-three thousand, three hundred ten".