20743231 has 4 divisors (see below), whose sum is σ = 21835000. Its totient is φ = 19651464.

The previous prime is 20743211. The next prime is 20743271. The reversal of 20743231 is 13234702.

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

It is a cyclic number.

It is not a de Polignac number, because 20743231 - 2⁷ = 20743103 is a prime.

It is a super-2 number, since 2×20743231² = 860563264638722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20743211) 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, 545856 + ... + 545893.

It is an arithmetic number, because the mean of its divisors is an integer number (5458750).

Almost surely, 2^20743231 is an apocalyptic number.

20743231 is a deficient number, since it is larger than the sum of its proper divisors (1091769).

20743231 is a wasteful number, since it uses less digits than its factorization.

20743231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1091768.

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

The square root of 20743231 is about 4554.4737346921. The cubic root of 20743231 is about 274.7633490257.

Adding to 20743231 its reverse (13234702), we get a palindrome (33977933).

The spelling of 20743231 in words is "twenty million, seven hundred forty-three thousand, two hundred thirty-one".