21928318 has 16 divisors (see below), whose sum is σ = 34744320. Its totient is φ = 10350936.

The previous prime is 21928303. The next prime is 21928327. The reversal of 21928318 is 81382912.

It is a super-2 number, since 2×21928318² = 961702260618248, 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 7 ways as a sum of consecutive naturals, for example, 12355 + ... + 14017.

It is an arithmetic number, because the mean of its divisors is an integer number (2171520).

Almost surely, 2^21928318 is an apocalyptic number.

21928318 is a deficient number, since it is larger than the sum of its proper divisors (12816002).

21928318 is a wasteful number, since it uses less digits than its factorization.

21928318 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2031.

The product of its digits is 6912, while the sum is 34.

The square root of 21928318 is about 4682.7681984057. The cubic root of 21928318 is about 279.8992749948.

The spelling of 21928318 in words is "twenty-one million, nine hundred twenty-eight thousand, three hundred eighteen".