997864961 has 2 divisors, whose sum is σ = 997864962. Its totient is φ = 997864960.

The previous prime is 997864949. The next prime is 997864979. The reversal of 997864961 is 169468799.

997864961 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 880012225 + 117852736 = 29665^2 + 10856^2 .

It is an emirp because it is prime and its reverse (169468799) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-997864961 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 997864961.

It is not a weakly prime, because it can be changed into another prime (997864261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 498932480 + 498932481.

It is an arithmetic number, because the mean of its divisors is an integer number (498932481).

Almost surely, 2^997864961 is an apocalyptic number.

It is an amenable number.

997864961 is a deficient number, since it is larger than the sum of its proper divisors (1).

997864961 is an equidigital number, since it uses as much as digits as its factorization.

997864961 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5878656, while the sum is 59.

The square root of 997864961 is about 31589.0006331318. Note that the first 3 decimals coincide. The cubic root of 997864961 is about 999.2878132438.

The spelling of 997864961 in words is "nine hundred ninety-seven million, eight hundred sixty-four thousand, nine hundred sixty-one".