20423440343 has 4 divisors (see below), whose sum is σ = 20808788328. Its totient is φ = 20038092360.

The previous prime is 20423440339. The next prime is 20423440351. The reversal of 20423440343 is 34304432402.

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 20423440343 - 2² = 20423440339 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20423440313) 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, 192673913 + ... + 192674018.

It is an arithmetic number, because the mean of its divisors is an integer number (5202197082).

Almost surely, 2^20423440343 is an apocalyptic number.

20423440343 is a deficient number, since it is larger than the sum of its proper divisors (385347985).

20423440343 is an equidigital number, since it uses as much as digits as its factorization.

20423440343 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 385347984.

The product of its (nonzero) digits is 27648, while the sum is 29.

Adding to 20423440343 its reverse (34304432402), we get a palindrome (54727872745).

The spelling of 20423440343 in words is "twenty billion, four hundred twenty-three million, four hundred forty thousand, three hundred forty-three".