20439445 has 8 divisors (see below), whose sum is σ = 26414136. Its totient is φ = 15093696.

The previous prime is 20439439. The next prime is 20439449. The reversal of 20439445 is 54493402.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 4 + 20439441 = 2^2 + 4521^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 20439445 - 2⁷ = 20439317 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20439449) 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, 157162 + ... + 157291.

It is an arithmetic number, because the mean of its divisors is an integer number (3301767).

Almost surely, 2^20439445 is an apocalyptic number.

It is an amenable number.

20439445 is a deficient number, since it is larger than the sum of its proper divisors (5974691).

20439445 is a wasteful number, since it uses less digits than its factorization.

20439445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 314471.

The product of its (nonzero) digits is 17280, while the sum is 31.

The square root of 20439445 is about 4521.0004423800. Note that the first 3 decimals coincide. The cubic root of 20439445 is about 273.4154381874.

The spelling of 20439445 in words is "twenty million, four hundred thirty-nine thousand, four hundred forty-five".