36581561 has 2 divisors, whose sum is σ = 36581562. Its totient is φ = 36581560.

The previous prime is 36581551. The next prime is 36581591. The reversal of 36581561 is 16518563.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 34810000 + 1771561 = 5900^2 + 1331^2 .

It is a cyclic number.

It is not a de Polignac number, because 36581561 - 2⁶ = 36581497 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (36581551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 18290780 + 18290781.

It is an arithmetic number, because the mean of its divisors is an integer number (18290781).

Almost surely, 2^36581561 is an apocalyptic number.

It is an amenable number.

36581561 is a deficient number, since it is larger than the sum of its proper divisors (1).

36581561 is an equidigital number, since it uses as much as digits as its factorization.

36581561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 21600, while the sum is 35.

The square root of 36581561 is about 6048.2692565725. The cubic root of 36581561 is about 331.9612652589.

The spelling of 36581561 in words is "thirty-six million, five hundred eighty-one thousand, five hundred sixty-one".