21968382 has 16 divisors (see below), whose sum is σ = 44218512. Its totient is φ = 7275840.

The previous prime is 21968371. The next prime is 21968383. The reversal of 21968382 is 28386912.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21968382.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21968383) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10719 + ... + 12602.

It is an arithmetic number, because the mean of its divisors is an integer number (2763657).

Almost surely, 2^21968382 is an apocalyptic number.

21968382 is an abundant number, since it is smaller than the sum of its proper divisors (22250130).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21968382 is a wasteful number, since it uses less digits than its factorization.

21968382 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23483.

The product of its digits is 41472, while the sum is 39.

The square root of 21968382 is about 4687.0440578258. The cubic root of 21968382 is about 280.0696340416.

The spelling of 21968382 in words is "twenty-one million, nine hundred sixty-eight thousand, three hundred eighty-two".