20431353 has 4 divisors (see below), whose sum is σ = 27241808. Its totient is φ = 13620900.

The previous prime is 20431343. The next prime is 20431381. The reversal of 20431353 is 35313402.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 20431353 - 2⁸ = 20431097 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20431303) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3405223 + ... + 3405228.

It is an arithmetic number, because the mean of its divisors is an integer number (6810452).

Almost surely, 2^20431353 is an apocalyptic number.

It is an amenable number.

20431353 is a deficient number, since it is larger than the sum of its proper divisors (6810455).

20431353 is an equidigital number, since it uses as much as digits as its factorization.

20431353 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6810454.

The product of its (nonzero) digits is 1080, while the sum is 21.

The square root of 20431353 is about 4520.1054191246. The cubic root of 20431353 is about 273.3793515949.

Adding to 20431353 its reverse (35313402), we get a palindrome (55744755).

The spelling of 20431353 in words is "twenty million, four hundred thirty-one thousand, three hundred fifty-three".