2001021433 has 2 divisors, whose sum is σ = 2001021434. Its totient is φ = 2001021432.

The previous prime is 2001021391. The next prime is 2001021481. The reversal of 2001021433 is 3341201002.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1999610089 + 1411344 = 44717^2 + 1188^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2001021433 is a prime.

It is not a weakly prime, because it can be changed into another prime (2001021493) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1000510716 + 1000510717.

It is an arithmetic number, because the mean of its divisors is an integer number (1000510717).

Almost surely, 2^2001021433 is an apocalyptic number.

It is an amenable number.

2001021433 is a deficient number, since it is larger than the sum of its proper divisors (1).

2001021433 is an equidigital number, since it uses as much as digits as its factorization.

2001021433 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 2001021433 is about 44732.7780603888. The cubic root of 2001021433 is about 1260.1355008808.

Adding to 2001021433 its reverse (3341201002), we get a palindrome (5342222435).

The spelling of 2001021433 in words is "two billion, one million, twenty-one thousand, four hundred thirty-three".