21944069 has 16 divisors (see below), whose sum is σ = 26611200. Its totient is φ = 17676144.

The previous prime is 21944057. The next prime is 21944081. The reversal of 21944069 is 96044912.

It is an interprime number because it is at equal distance from previous prime (21944057) and next prime (21944081).

It is a cyclic number.

It is not a de Polignac number, because 21944069 - 2⁸ = 21943813 is a prime.

It is a super-2 number, since 2×21944069² = 963084328553522, which contains 22 as substring.

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

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17894 + ... + 19080.

It is an arithmetic number, because the mean of its divisors is an integer number (1663200).

Almost surely, 2^21944069 is an apocalyptic number.

It is an amenable number.

21944069 is a deficient number, since it is larger than the sum of its proper divisors (4667131).

21944069 is a wasteful number, since it uses less digits than its factorization.

21944069 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1352.

The product of its (nonzero) digits is 15552, while the sum is 35.

The square root of 21944069 is about 4684.4497008720. The cubic root of 21944069 is about 279.9662757002.

The spelling of 21944069 in words is "twenty-one million, nine hundred forty-four thousand, sixty-nine".