3561564581 has 2 divisors, whose sum is σ = 3561564582. Its totient is φ = 3561564580.

The previous prime is 3561564571. The next prime is 3561564599. The reversal of 3561564581 is 1854651653.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2895408481 + 666156100 = 53809^2 + 25810^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3561564581 is a prime.

It is a super-2 number, since 2×3561564581² = 25369484529267411122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3561564541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1780782290 + 1780782291.

It is an arithmetic number, because the mean of its divisors is an integer number (1780782291).

Almost surely, 2^3561564581 is an apocalyptic number.

It is an amenable number.

3561564581 is a deficient number, since it is larger than the sum of its proper divisors (1).

3561564581 is an equidigital number, since it uses as much as digits as its factorization.

3561564581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 432000, while the sum is 44.

The square root of 3561564581 is about 59678.8453390311. The cubic root of 3561564581 is about 1527.1449999380.

The spelling of 3561564581 in words is "three billion, five hundred sixty-one million, five hundred sixty-four thousand, five hundred eighty-one".