21794439 has 4 divisors (see below), whose sum is σ = 29059256. Its totient is φ = 14529624.

The previous prime is 21794431. The next prime is 21794447. The reversal of 21794439 is 93449712.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (21794431) and next prime (21794447).

It is not a de Polignac number, because 21794439 - 2³ = 21794431 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21794397 and 21794406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21794431) 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, 3632404 + ... + 3632409.

It is an arithmetic number, because the mean of its divisors is an integer number (7264814).

Almost surely, 2^21794439 is an apocalyptic number.

21794439 is a deficient number, since it is larger than the sum of its proper divisors (7264817).

21794439 is an equidigital number, since it uses as much as digits as its factorization.

21794439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7264816.

The product of its digits is 54432, while the sum is 39.

The square root of 21794439 is about 4668.4514563183. The cubic root of 21794439 is about 279.3284886211.

The spelling of 21794439 in words is "twenty-one million, seven hundred ninety-four thousand, four hundred thirty-nine".