997547801 has 2 divisors, whose sum is σ = 997547802. Its totient is φ = 997547800.

The previous prime is 997547783. The next prime is 997547809. The reversal of 997547801 is 108745799.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 769507600 + 228040201 = 27740^2 + 15101^2 .

It is a cyclic number.

It is not a de Polignac number, because 997547801 - 2¹⁴ = 997531417 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 997547801.

It is not a weakly prime, because it can be changed into another prime (997547809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 498773900 + 498773901.

It is an arithmetic number, because the mean of its divisors is an integer number (498773901).

Almost surely, 2^997547801 is an apocalyptic number.

It is an amenable number.

997547801 is a deficient number, since it is larger than the sum of its proper divisors (1).

997547801 is an equidigital number, since it uses as much as digits as its factorization.

997547801 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 635040, while the sum is 50.

The square root of 997547801 is about 31583.9801323392. The cubic root of 997547801 is about 999.1819312794.

The spelling of 997547801 in words is "nine hundred ninety-seven million, five hundred forty-seven thousand, eight hundred one".