20171439 has 6 divisors (see below), whose sum is σ = 29136536. Its totient is φ = 13447620.

The previous prime is 20171423. The next prime is 20171449. The reversal of 20171439 is 93417102.

It is not a de Polignac number, because 20171439 - 2⁴ = 20171423 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 (20171449) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1120627 + ... + 1120644.

Almost surely, 2^20171439 is an apocalyptic number.

20171439 is a deficient number, since it is larger than the sum of its proper divisors (8965097).

20171439 is a wasteful number, since it uses less digits than its factorization.

20171439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2241277 (or 2241274 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 27.

The square root of 20171439 is about 4491.2625173775. The cubic root of 20171439 is about 272.2151511021.

The spelling of 20171439 in words is "twenty million, one hundred seventy-one thousand, four hundred thirty-nine".