20439438 has 8 divisors (see below), whose sum is σ = 40878888. Its totient is φ = 6813144.

The previous prime is 20439379. The next prime is 20439439. The reversal of 20439438 is 83493402.

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

20439438 is an admirable number.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 20439399 and 20439408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20439439) 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, 1703281 + ... + 1703292.

It is an arithmetic number, because the mean of its divisors is an integer number (5109861).

Almost surely, 2^20439438 is an apocalyptic number.

20439438 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

20439438 is a wasteful number, since it uses less digits than its factorization.

20439438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3406578.

The product of its (nonzero) digits is 20736, while the sum is 33.

The square root of 20439438 is about 4520.9996682150. Note that the first 3 decimals coincide. The cubic root of 20439438 is about 273.4154069747.

The spelling of 20439438 in words is "twenty million, four hundred thirty-nine thousand, four hundred thirty-eight".