20423243 has 4 divisors (see below), whose sum is σ = 20432448. Its totient is φ = 20414040.

The previous prime is 20423231. The next prime is 20423257. The reversal of 20423243 is 34232402.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20423243 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20423213) 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, 998 + ... + 6468.

It is an arithmetic number, because the mean of its divisors is an integer number (5108112).

Almost surely, 2^20423243 is an apocalyptic number.

20423243 is a deficient number, since it is larger than the sum of its proper divisors (9205).

20423243 is an equidigital number, since it uses as much as digits as its factorization.

20423243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9204.

The product of its (nonzero) digits is 1152, while the sum is 20.

The square root of 20423243 is about 4519.2082271124. The cubic root of 20423243 is about 273.3431751695.

Adding to 20423243 its reverse (34232402), we get a palindrome (54655645).

The spelling of 20423243 in words is "twenty million, four hundred twenty-three thousand, two hundred forty-three".