21001143243 has 8 divisors (see below), whose sum is σ = 28002977856. Its totient is φ = 14000035400.

The previous prime is 21001143227. The next prime is 21001143253. The reversal of 21001143243 is 34234110012.

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 21001143243 - 2⁴ = 21001143227 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21001143253) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 110253 + ... + 232718.

It is an arithmetic number, because the mean of its divisors is an integer number (3500372232).

Almost surely, 2^21001143243 is an apocalyptic number.

21001143243 is a deficient number, since it is larger than the sum of its proper divisors (7001834613).

21001143243 is a wasteful number, since it uses less digits than its factorization.

21001143243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 363385.

The product of its (nonzero) digits is 576, while the sum is 21.

Adding to 21001143243 its reverse (34234110012), we get a palindrome (55235253255).

The spelling of 21001143243 in words is "twenty-one billion, one million, one hundred forty-three thousand, two hundred forty-three".