20405450543 has 4 divisors (see below), whose sum is σ = 20414445960. Its totient is φ = 20396455128.

The previous prime is 20405450449. The next prime is 20405450561. The reversal of 20405450543 is 34505450402.

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 20405450543 - 2²⁶ = 20338341679 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 (20405450743) 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, 4494305 + ... + 4498842.

It is an arithmetic number, because the mean of its divisors is an integer number (5103611490).

Almost surely, 2^20405450543 is an apocalyptic number.

20405450543 is a deficient number, since it is larger than the sum of its proper divisors (8995417).

20405450543 is an equidigital number, since it uses as much as digits as its factorization.

20405450543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8995416.

The product of its (nonzero) digits is 48000, while the sum is 32.

The spelling of 20405450543 in words is "twenty billion, four hundred five million, four hundred fifty thousand, five hundred forty-three".