814531561 has 2 divisors, whose sum is σ = 814531562. Its totient is φ = 814531560.

The previous prime is 814531547. The next prime is 814531657. The reversal of 814531561 is 165135418.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 550793961 + 263737600 = 23469^2 + 16240^2 .

It is a cyclic number.

It is not a de Polignac number, because 814531561 - 2¹⁹ = 814007273 is a prime.

It is not a weakly prime, because it can be changed into another prime (814531511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 407265780 + 407265781.

It is an arithmetic number, because the mean of its divisors is an integer number (407265781).

Almost surely, 2^814531561 is an apocalyptic number.

It is an amenable number.

814531561 is a deficient number, since it is larger than the sum of its proper divisors (1).

814531561 is an equidigital number, since it uses as much as digits as its factorization.

814531561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 14400, while the sum is 34.

The square root of 814531561 is about 28539.9993167484. Note that the first 3 decimals coincide. The cubic root of 814531561 is about 933.9048674479.

Adding to 814531561 its reverse (165135418), we get a palindrome (979666979).

The spelling of 814531561 in words is "eight hundred fourteen million, five hundred thirty-one thousand, five hundred sixty-one".