20731107 has 4 divisors (see below), whose sum is σ = 27641480. Its totient is φ = 13820736.

The previous prime is 20731097. The next prime is 20731121. The reversal of 20731107 is 70113702.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 20731107 - 2⁴ = 20731091 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20731127) 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 3 ways as a sum of consecutive naturals, for example, 3455182 + ... + 3455187.

It is an arithmetic number, because the mean of its divisors is an integer number (6910370).

Almost surely, 2^20731107 is an apocalyptic number.

20731107 is a deficient number, since it is larger than the sum of its proper divisors (6910373).

20731107 is an equidigital number, since it uses as much as digits as its factorization.

20731107 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6910372.

The product of its (nonzero) digits is 294, while the sum is 21.

The square root of 20731107 is about 4553.1425411467. The cubic root of 20731107 is about 274.7098073818.

Adding to 20731107 its reverse (70113702), we get a palindrome (90844809).

The spelling of 20731107 in words is "twenty million, seven hundred thirty-one thousand, one hundred seven".