20400243143 has 4 divisors (see below), whose sum is σ = 23314563600. Its totient is φ = 17485922688.

The previous prime is 20400243131. The next prime is 20400243161. The reversal of 20400243143 is 34134200402.

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 20400243143 - 2¹² = 20400239047 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 (20400243443) 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, 1457160218 + ... + 1457160231.

It is an arithmetic number, because the mean of its divisors is an integer number (5828640900).

Almost surely, 2^20400243143 is an apocalyptic number.

20400243143 is a deficient number, since it is larger than the sum of its proper divisors (2914320457).

20400243143 is an equidigital number, since it uses as much as digits as its factorization.

20400243143 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2914320456.

The product of its (nonzero) digits is 2304, while the sum is 23.

Adding to 20400243143 its reverse (34134200402), we get a palindrome (54534443545).

The spelling of 20400243143 in words is "twenty billion, four hundred million, two hundred forty-three thousand, one hundred forty-three".