36611546581 has 2 divisors, whose sum is σ = 36611546582. Its totient is φ = 36611546580.

The previous prime is 36611546549. The next prime is 36611546663. The reversal of 36611546581 is 18564511663.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 35274474225 + 1337072356 = 187815^2 + 36566^2 .

It is a cyclic number.

It is not a de Polignac number, because 36611546581 - 2⁵ = 36611546549 is a prime.

It is a super-2 number, since 2×36611546581² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (36611546281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 18305773290 + 18305773291.

It is an arithmetic number, because the mean of its divisors is an integer number (18305773291).

Almost surely, 2^36611546581 is an apocalyptic number.

It is an amenable number.

36611546581 is a deficient number, since it is larger than the sum of its proper divisors (1).

36611546581 is an equidigital number, since it uses as much as digits as its factorization.

36611546581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 518400, while the sum is 46.

The spelling of 36611546581 in words is "thirty-six billion, six hundred eleven million, five hundred forty-six thousand, five hundred eighty-one".