997287171218 has 18 divisors (see below), whose sum is σ = 1619883836469. Its totient is φ = 460277912952.

The previous prime is 997287171169. The next prime is 997287171311. The reversal of 997287171218 is 812171782799.

It can be written as a sum of positive squares in 2 ways, for example, as 852710036929 + 144577134289 = 923423^2 + 380233^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=706147.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 18332663 + ... + 18386981.

Almost surely, 2^997287171218 is an apocalyptic number.

997287171218 is a deficient number, since it is larger than the sum of its proper divisors (622596665251).

997287171218 is an frugal number, since it uses more digits than its factorization.

997287171218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108666 (or 54334 counting only the distinct ones).

The product of its digits is 7112448, while the sum is 62.

The spelling of 997287171218 in words is "nine hundred ninety-seven billion, two hundred eighty-seven million, one hundred seventy-one thousand, two hundred eighteen".