21982316 has 12 divisors (see below), whose sum is σ = 40493880. Its totient is φ = 10412640.

The previous prime is 21982313. The next prime is 21982339. The reversal of 21982316 is 61328912.

It is not an unprimeable number, because it can be changed into a prime (21982313) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 144545 + ... + 144696.

It is an arithmetic number, because the mean of its divisors is an integer number (3374490).

Almost surely, 2^21982316 is an apocalyptic number.

It is an amenable number.

21982316 is a deficient number, since it is larger than the sum of its proper divisors (18511564).

21982316 is a wasteful number, since it uses less digits than its factorization.

21982316 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 289264 (or 289262 counting only the distinct ones).

The product of its digits is 5184, while the sum is 32.

The square root of 21982316 is about 4688.5302601135. The cubic root of 21982316 is about 280.1288352683.

The spelling of 21982316 in words is "twenty-one million, nine hundred eighty-two thousand, three hundred sixteen".