21967344 has 240 divisors, whose sum is σ = 78407680. Its totient is φ = 5598720.

The previous prime is 21967343. The next prime is 21967397. The reversal of 21967344 is 44376912.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

Its product of digits (36288) is a multiple of the sum of its prime factors (108).

It is a zygodrome in base 11.

It is a junction number, because it is equal to n+sod(n) for n = 21967299 and 21967308.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21967343) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 593694 + ... + 593730.

Almost surely, 2^21967344 is an apocalyptic number.

21967344 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21967344, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39203840).

21967344 is an abundant number, since it is smaller than the sum of its proper divisors (56440336).

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

21967344 is a wasteful number, since it uses less digits than its factorization.

21967344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108 (or 99 counting only the distinct ones).

The product of its digits is 36288, while the sum is 36.

The square root of 21967344 is about 4686.9333257472. The cubic root of 21967344 is about 280.0652229011.

The spelling of 21967344 in words is "twenty-one million, nine hundred sixty-seven thousand, three hundred forty-four".