20009431 has 6 divisors (see below), whose sum is σ = 21667200. Its totient is φ = 18470088.

The previous prime is 20009419. The next prime is 20009441. The reversal of 20009431 is 13490002.

It is not a de Polignac number, because 20009431 - 2¹³ = 20001239 is a prime.

It is a super-2 number, since 2×20009431² = 800754657887522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20009399 and 20009408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20009411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 59031 + ... + 59368.

It is an arithmetic number, because the mean of its divisors is an integer number (3611200).

Almost surely, 2^20009431 is an apocalyptic number.

20009431 is a deficient number, since it is larger than the sum of its proper divisors (1657769).

20009431 is a wasteful number, since it uses less digits than its factorization.

20009431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 118425 (or 118412 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 19.

The square root of 20009431 is about 4473.1902485810. The cubic root of 20009431 is about 271.4844210757.

Adding to 20009431 its reverse (13490002), we get a palindrome (33499433).

The spelling of 20009431 in words is "twenty million, nine thousand, four hundred thirty-one".