21427003543 has 8 divisors (see below), whose sum is σ = 23382208656. Its totient is φ = 19473014400.

The previous prime is 21427003537. The next prime is 21427003567. The reversal of 21427003543 is 34530072412.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21427003543 - 2²⁹ = 20890132631 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 (21427003523) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 266946 + ... + 337807.

It is an arithmetic number, because the mean of its divisors is an integer number (2922776082).

Almost surely, 2^21427003543 is an apocalyptic number.

21427003543 is a deficient number, since it is larger than the sum of its proper divisors (1955205113).

21427003543 is a wasteful number, since it uses less digits than its factorization.

21427003543 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 607985.

The product of its (nonzero) digits is 20160, while the sum is 31.

Adding to 21427003543 its reverse (34530072412), we get a palindrome (55957075955).

The spelling of 21427003543 in words is "twenty-one billion, four hundred twenty-seven million, three thousand, five hundred forty-three".