2002611581 has 2 divisors, whose sum is σ = 2002611582. Its totient is φ = 2002611580.

The previous prime is 2002611521. The next prime is 2002611599. The reversal of 2002611581 is 1851162002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1568556025 + 434055556 = 39605^2 + 20834^2 .

It is a cyclic number.

It is not a de Polignac number, because 2002611581 - 2³⁰ = 928869757 is a prime.

It is a super-2 number, since 2×2002611581² = 8020906288710639122, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 2002611581.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2002611511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1001305790 + 1001305791.

It is an arithmetic number, because the mean of its divisors is an integer number (1001305791).

Almost surely, 2^2002611581 is an apocalyptic number.

It is an amenable number.

2002611581 is a deficient number, since it is larger than the sum of its proper divisors (1).

2002611581 is an equidigital number, since it uses as much as digits as its factorization.

2002611581 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 960, while the sum is 26.

The square root of 2002611581 is about 44750.5483877014. The cubic root of 2002611581 is about 1260.4692090163.

Adding to 2002611581 its reverse (1851162002), we get a palindrome (3853773583).

The spelling of 2002611581 in words is "two billion, two million, six hundred eleven thousand, five hundred eighty-one".