20731243 has 16 divisors (see below), whose sum is σ = 22982400. Its totient is φ = 18583200.

The previous prime is 20731241. The next prime is 20731247. The reversal of 20731243 is 34213702.

It is a cyclic number.

It is not a de Polignac number, because 20731243 - 2¹ = 20731241 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20731241) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 115728 + ... + 115906.

It is an arithmetic number, because the mean of its divisors is an integer number (1436400).

Almost surely, 2^20731243 is an apocalyptic number.

20731243 is a deficient number, since it is larger than the sum of its proper divisors (2251157).

20731243 is a wasteful number, since it uses less digits than its factorization.

20731243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 402.

The product of its (nonzero) digits is 1008, while the sum is 22.

The square root of 20731243 is about 4553.1574758622. The cubic root of 20731243 is about 274.7104080966.

Adding to 20731243 its reverse (34213702), we get a palindrome (54944945).

The spelling of 20731243 in words is "twenty million, seven hundred thirty-one thousand, two hundred forty-three".