21001141243 has 2 divisors, whose sum is σ = 21001141244. Its totient is φ = 21001141242.

The previous prime is 21001141241. The next prime is 21001141247. The reversal of 21001141243 is 34214110012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21001141243 - 2¹ = 21001141241 is a prime.

Together with 21001141241, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21001141243.

It is not a weakly prime, because it can be changed into another prime (21001141241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500570621 + 10500570622.

It is an arithmetic number, because the mean of its divisors is an integer number (10500570622).

Almost surely, 2^21001141243 is an apocalyptic number.

21001141243 is a deficient number, since it is larger than the sum of its proper divisors (1).

21001141243 is an equidigital number, since it uses as much as digits as its factorization.

21001141243 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 192, while the sum is 19.

Adding to 21001141243 its reverse (34214110012), we get a palindrome (55215251255).

The spelling of 21001141243 in words is "twenty-one billion, one million, one hundred forty-one thousand, two hundred forty-three".