18435731641 has 2 divisors, whose sum is σ = 18435731642. Its totient is φ = 18435731640.

The previous prime is 18435731609. The next prime is 18435731653. The reversal of 18435731641 is 14613753481.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17207930041 + 1227801600 = 131179^2 + 35040^2 .

It is an emirp because it is prime and its reverse (14613753481) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18435731641 - 2⁵ = 18435731609 is a prime.

It is a super-2 number, since 2×18435731641² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (18435731681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9217865820 + 9217865821.

It is an arithmetic number, because the mean of its divisors is an integer number (9217865821).

Almost surely, 2^18435731641 is an apocalyptic number.

It is an amenable number.

18435731641 is a deficient number, since it is larger than the sum of its proper divisors (1).

18435731641 is an equidigital number, since it uses as much as digits as its factorization.

18435731641 is an evil number, because the sum of its binary digits is even.

The product of its digits is 241920, while the sum is 43.

The spelling of 18435731641 in words is "eighteen billion, four hundred thirty-five million, seven hundred thirty-one thousand, six hundred forty-one".