18604581761 has 2 divisors, whose sum is σ = 18604581762. Its totient is φ = 18604581760.

The previous prime is 18604581733. The next prime is 18604581791. The reversal of 18604581761 is 16718540681.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10864101361 + 7740480400 = 104231^2 + 87980^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18604581761 is a prime.

It is a super-2 number, since 2×18604581761² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (18604581701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9302290880 + 9302290881.

It is an arithmetic number, because the mean of its divisors is an integer number (9302290881).

Almost surely, 2^18604581761 is an apocalyptic number.

It is an amenable number.

18604581761 is a deficient number, since it is larger than the sum of its proper divisors (1).

18604581761 is an equidigital number, since it uses as much as digits as its factorization.

18604581761 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 322560, while the sum is 47.

The spelling of 18604581761 in words is "eighteen billion, six hundred four million, five hundred eighty-one thousand, seven hundred sixty-one".