20387439 has 6 divisors (see below), whose sum is σ = 29448536. Its totient is φ = 13591620.

The previous prime is 20387431. The next prime is 20387441. The reversal of 20387439 is 93478302.

It is not a de Polignac number, because 20387439 - 2³ = 20387431 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 (20387431) 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, 1132627 + ... + 1132644.

Almost surely, 2^20387439 is an apocalyptic number.

20387439 is a deficient number, since it is larger than the sum of its proper divisors (9061097).

20387439 is a wasteful number, since it uses less digits than its factorization.

20387439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2265277 (or 2265274 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 36.

The square root of 20387439 is about 4515.2451760674. The cubic root of 20387439 is about 273.1833490392.

The spelling of 20387439 in words is "twenty million, three hundred eighty-seven thousand, four hundred thirty-nine".