18924645997 has 2 divisors, whose sum is σ = 18924645998. Its totient is φ = 18924645996.

The previous prime is 18924645991. The next prime is 18924646093. The reversal of 18924645997 is 79954642981.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11283963076 + 7640682921 = 106226^2 + 87411^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18924645997 is a prime.

It is a super-3 number, since 3×18924645997³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18924645991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9462322998 + 9462322999.

It is an arithmetic number, because the mean of its divisors is an integer number (9462322999).

Almost surely, 2^18924645997 is an apocalyptic number.

It is an amenable number.

18924645997 is a deficient number, since it is larger than the sum of its proper divisors (1).

18924645997 is an equidigital number, since it uses as much as digits as its factorization.

18924645997 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 39191040, while the sum is 64.

The spelling of 18924645997 in words is "eighteen billion, nine hundred twenty-four million, six hundred forty-five thousand, nine hundred ninety-seven".