4001330561 has 2 divisors, whose sum is σ = 4001330562. Its totient is φ = 4001330560.

The previous prime is 4001330533. The next prime is 4001330587. The reversal of 4001330561 is 1650331004.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4001321536 + 9025 = 63256^2 + 95^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-4001330561 is a prime.

It is not a weakly prime, because it can be changed into another prime (4001330461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2000665280 + 2000665281.

It is an arithmetic number, because the mean of its divisors is an integer number (2000665281).

Almost surely, 2^4001330561 is an apocalyptic number.

It is an amenable number.

4001330561 is a deficient number, since it is larger than the sum of its proper divisors (1).

4001330561 is an equidigital number, since it uses as much as digits as its factorization.

4001330561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1080, while the sum is 23.

The square root of 4001330561 is about 63256.0713370661. The cubic root of 4001330561 is about 1587.5770436166.

Adding to 4001330561 its reverse (1650331004), we get a palindrome (5651661565).

The spelling of 4001330561 in words is "four billion, one million, three hundred thirty thousand, five hundred sixty-one".