1031561 has 2 divisors, whose sum is σ = 1031562. Its totient is φ = 1031560.

The previous prime is 1031549. The next prime is 1031593. The reversal of 1031561 is 1651301.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 712336 + 319225 = 844^2 + 565^2 .

It is a cyclic number.

It is not a de Polignac number, because 1031561 - 2¹⁰ = 1030537 is a prime.

It is a plaindrome in base 15.

It is not a weakly prime, because it can be changed into another prime (1031521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 515780 + 515781.

It is an arithmetic number, because the mean of its divisors is an integer number (515781).

2^1031561 is an apocalyptic number.

It is an amenable number.

1031561 is a deficient number, since it is larger than the sum of its proper divisors (1).

1031561 is an equidigital number, since it uses as much as digits as its factorization.

1031561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 90, while the sum is 17.

The square root of 1031561 is about 1015.6579148513. The cubic root of 1031561 is about 101.0411556616.

Adding to 1031561 its reverse (1651301), we get a palindrome (2682862).

The spelling of 1031561 in words is "one million, thirty-one thousand, five hundred sixty-one".