21401143243 has 4 divisors (see below), whose sum is σ = 22660034040. Its totient is φ = 20142252448.

The previous prime is 21401143237. The next prime is 21401143261. The reversal of 21401143243 is 34234110412.

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 21401143243 - 2²⁵ = 21367588811 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21401141243) 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, 629445373 + ... + 629445406.

It is an arithmetic number, because the mean of its divisors is an integer number (5665008510).

Almost surely, 2^21401143243 is an apocalyptic number.

21401143243 is a deficient number, since it is larger than the sum of its proper divisors (1258890797).

21401143243 is a wasteful number, since it uses less digits than its factorization.

21401143243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1258890796.

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

Adding to 21401143243 its reverse (34234110412), we get a palindrome (55635253655).

The spelling of 21401143243 in words is "twenty-one billion, four hundred one million, one hundred forty-three thousand, two hundred forty-three".