21944039 has 8 divisors (see below), whose sum is σ = 24447360. Its totient is φ = 19557216.

The previous prime is 21944029. The next prime is 21944057. The reversal of 21944039 is 93044912.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21944039 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21943996 and 21944014.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21944009) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28727 + ... + 29480.

It is an arithmetic number, because the mean of its divisors is an integer number (3055920).

Almost surely, 2^21944039 is an apocalyptic number.

21944039 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

21944039 is a deficient number, since it is larger than the sum of its proper divisors (2503321).

21944039 is a wasteful number, since it uses less digits than its factorization.

21944039 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58249.

The product of its (nonzero) digits is 7776, while the sum is 32.

The square root of 21944039 is about 4684.4464987872. The cubic root of 21944039 is about 279.9661481184.

The spelling of 21944039 in words is "twenty-one million, nine hundred forty-four thousand, thirty-nine".