8531561 has 2 divisors, whose sum is σ = 8531562. Its totient is φ = 8531560.

The previous prime is 8531543. The next prime is 8531609. The reversal of 8531561 is 1651358.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6760000 + 1771561 = 2600^2 + 1331^2 .

It is a cyclic number.

It is not a de Polignac number, because 8531561 - 2¹⁰ = 8530537 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (8531531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4265780 + 4265781.

It is an arithmetic number, because the mean of its divisors is an integer number (4265781).

Almost surely, 2^8531561 is an apocalyptic number.

It is an amenable number.

8531561 is a deficient number, since it is larger than the sum of its proper divisors (1).

8531561 is an equidigital number, since it uses as much as digits as its factorization.

8531561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3600, while the sum is 29.

The square root of 8531561 is about 2920.8835991871. The cubic root of 8531561 is about 204.3350335363.

The spelling of 8531561 in words is "eight million, five hundred thirty-one thousand, five hundred sixty-one".