997000561 has 2 divisors, whose sum is σ = 997000562. Its totient is φ = 997000560.

The previous prime is 997000553. The next prime is 997000583. The reversal of 997000561 is 165000799.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 982446336 + 14554225 = 31344^2 + 3815^2 .

It is a cyclic number.

It is not a de Polignac number, because 997000561 - 2³ = 997000553 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 997000561.

It is not a weakly prime, because it can be changed into another prime (997000591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 498500280 + 498500281.

It is an arithmetic number, because the mean of its divisors is an integer number (498500281).

Almost surely, 2^997000561 is an apocalyptic number.

It is an amenable number.

997000561 is a deficient number, since it is larger than the sum of its proper divisors (1).

997000561 is an equidigital number, since it uses as much as digits as its factorization.

997000561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17010, while the sum is 37.

The square root of 997000561 is about 31575.3156912168. The cubic root of 997000561 is about 998.9991857049. Note that the first 3 decimals are identical.

The spelling of 997000561 in words is "nine hundred ninety-seven million, five hundred sixty-one", and thus it is an aban number.