20001021221143 has 2 divisors, whose sum is σ = 20001021221144. Its totient is φ = 20001021221142.

The previous prime is 20001021221099. The next prime is 20001021221147. The reversal of 20001021221143 is 34112212010002.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20001021221143 is a prime.

It is a super-2 number, since 2×20001021221143² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20001021221143.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20001021221147) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10000510610571 + 10000510610572.

It is an arithmetic number, because the mean of its divisors is an integer number (10000510610572).

Almost surely, 2^{20001021221143} is an apocalyptic number.

20001021221143 is a deficient number, since it is larger than the sum of its proper divisors (1).

20001021221143 is an equidigital number, since it uses as much as digits as its factorization.

20001021221143 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 20001021221143 its reverse (34112212010002), we get a palindrome (54113233231145).

The spelling of 20001021221143 in words is "twenty trillion, one billion, twenty-one million, two hundred twenty-one thousand, one hundred forty-three".