21404532543 has 4 divisors (see below), whose sum is σ = 28539376728. Its totient is φ = 14269688360.

The previous prime is 21404532511. The next prime is 21404532547. The reversal of 21404532543 is 34523540412.

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 21404532543 - 2⁵ = 21404532511 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21404532547) 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, 3567422088 + ... + 3567422093.

It is an arithmetic number, because the mean of its divisors is an integer number (7134844182).

Almost surely, 2^21404532543 is an apocalyptic number.

21404532543 is a deficient number, since it is larger than the sum of its proper divisors (7134844185).

21404532543 is an equidigital number, since it uses as much as digits as its factorization.

21404532543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7134844184.

The product of its (nonzero) digits is 57600, while the sum is 33.

The spelling of 21404532543 in words is "twenty-one billion, four hundred four million, five hundred thirty-two thousand, five hundred forty-three".