997485809 has 2 divisors, whose sum is σ = 997485810. Its totient is φ = 997485808.

The previous prime is 997485803. The next prime is 997485817. The reversal of 997485809 is 908584799.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 933485809 + 64000000 = 30553^2 + 8000^2 .

It is a cyclic number.

It is not a de Polignac number, because 997485809 - 2⁴ = 997485793 is a prime.

It is not a weakly prime, because it can be changed into another prime (997485803) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 498742904 + 498742905.

It is an arithmetic number, because the mean of its divisors is an integer number (498742905).

Almost surely, 2^997485809 is an apocalyptic number.

It is an amenable number.

997485809 is a deficient number, since it is larger than the sum of its proper divisors (1).

997485809 is an equidigital number, since it uses as much as digits as its factorization.

997485809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6531840, while the sum is 59.

The square root of 997485809 is about 31582.9987334958. The cubic root of 997485809 is about 999.1612330000.

The spelling of 997485809 in words is "nine hundred ninety-seven million, four hundred eighty-five thousand, eight hundred nine".