1002002021281 has 2 divisors, whose sum is σ = 1002002021282. Its totient is φ = 1002002021280.

The previous prime is 1002002021263. The next prime is 1002002021297. The reversal of 1002002021281 is 1821202002001.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 604996174225 + 397005847056 = 777815^2 + 630084^2 .

It is a cyclic number.

It is not a de Polignac number, because 1002002021281 - 2²¹ = 1001999924129 is a prime.

It is a super-2 number, since 2×1002002021281² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1002032021281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 501001010640 + 501001010641.

It is an arithmetic number, because the mean of its divisors is an integer number (501001010641).

Almost surely, 2^{1002002021281} is an apocalyptic number.

It is an amenable number.

1002002021281 is a deficient number, since it is larger than the sum of its proper divisors (1).

1002002021281 is an equidigital number, since it uses as much as digits as its factorization.

1002002021281 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 1002002021281 its reverse (1821202002001), we get a palindrome (2823204023282).

The spelling of 1002002021281 in words is "one trillion, two billion, two million, twenty-one thousand, two hundred eighty-one".