21002140433 has 2 divisors, whose sum is σ = 21002140434. Its totient is φ = 21002140432.

The previous prime is 21002140427. The next prime is 21002140469. The reversal of 21002140433 is 33404120012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17704165249 + 3297975184 = 133057^2 + 57428^2 .

It is a cyclic number.

It is not a de Polignac number, because 21002140433 - 2⁴ = 21002140417 is a prime.

It is not a weakly prime, because it can be changed into another prime (21002140403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10501070216 + 10501070217.

It is an arithmetic number, because the mean of its divisors is an integer number (10501070217).

Almost surely, 2^21002140433 is an apocalyptic number.

It is an amenable number.

21002140433 is a deficient number, since it is larger than the sum of its proper divisors (1).

21002140433 is an equidigital number, since it uses as much as digits as its factorization.

21002140433 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 576, while the sum is 20.

Adding to 21002140433 its reverse (33404120012), we get a palindrome (54406260445).

The spelling of 21002140433 in words is "twenty-one billion, two million, one hundred forty thousand, four hundred thirty-three".