18551337641 has 2 divisors, whose sum is σ = 18551337642. Its totient is φ = 18551337640.

The previous prime is 18551337599. The next prime is 18551337653. The reversal of 18551337641 is 14673315581.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15865921600 + 2685416041 = 125960^2 + 51821^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18551337641 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 18551337592 and 18551337601.

It is not a weakly prime, because it can be changed into another prime (18551337341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9275668820 + 9275668821.

It is an arithmetic number, because the mean of its divisors is an integer number (9275668821).

Almost surely, 2^18551337641 is an apocalyptic number.

It is an amenable number.

18551337641 is a deficient number, since it is larger than the sum of its proper divisors (1).

18551337641 is an equidigital number, since it uses as much as digits as its factorization.

18551337641 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 302400, while the sum is 44.

The spelling of 18551337641 in words is "eighteen billion, five hundred fifty-one million, three hundred thirty-seven thousand, six hundred forty-one".