21013142443 has 4 divisors (see below), whose sum is σ = 21018645648. Its totient is φ = 21007639240.

The previous prime is 21013142431. The next prime is 21013142459. The reversal of 21013142443 is 34424131012.

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 21013142443 - 2³³ = 12423207851 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21013140443) 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, 2745871 + ... + 2753512.

It is an arithmetic number, because the mean of its divisors is an integer number (5254661412).

Almost surely, 2^21013142443 is an apocalyptic number.

21013142443 is a deficient number, since it is larger than the sum of its proper divisors (5503205).

21013142443 is an equidigital number, since it uses as much as digits as its factorization.

21013142443 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5503204.

The product of its (nonzero) digits is 2304, while the sum is 25.

Adding to 21013142443 its reverse (34424131012), we get a palindrome (55437273455).

The spelling of 21013142443 in words is "twenty-one billion, thirteen million, one hundred forty-two thousand, four hundred forty-three".