997918289 has 2 divisors, whose sum is σ = 997918290. Its totient is φ = 997918288.

The previous prime is 997918223. The next prime is 997918331. The reversal of 997918289 is 982819799.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 887563264 + 110355025 = 29792^2 + 10505^2 .

It is a cyclic number.

It is not a de Polignac number, because 997918289 - 2¹² = 997914193 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (997911289) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 498959144 + 498959145.

It is an arithmetic number, because the mean of its divisors is an integer number (498959145).

Almost surely, 2^997918289 is an apocalyptic number.

It is an amenable number.

997918289 is a deficient number, since it is larger than the sum of its proper divisors (1).

997918289 is an equidigital number, since it uses as much as digits as its factorization.

997918289 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5878656, while the sum is 62.

The square root of 997918289 is about 31589.8447131353. The cubic root of 997918289 is about 999.3056142734.

The spelling of 997918289 in words is "nine hundred ninety-seven million, nine hundred eighteen thousand, two hundred eighty-nine".