997549121 has 2 divisors, whose sum is σ = 997549122. Its totient is φ = 997549120.

The previous prime is 997549099. The next prime is 997549127. The reversal of 997549121 is 121945799.

997549121 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 990990400 + 6558721 = 31480^2 + 2561^2 .

It is an emirp because it is prime and its reverse (121945799) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 997549121 - 2⁶ = 997549057 is a prime.

It is not a weakly prime, because it can be changed into another prime (997549127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 498774560 + 498774561.

It is an arithmetic number, because the mean of its divisors is an integer number (498774561).

Almost surely, 2^997549121 is an apocalyptic number.

It is an amenable number.

997549121 is a deficient number, since it is larger than the sum of its proper divisors (1).

997549121 is an equidigital number, since it uses as much as digits as its factorization.

997549121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 204120, while the sum is 47.

The square root of 997549121 is about 31584.0010290020. The cubic root of 997549121 is about 999.1823720000.

The spelling of 997549121 in words is "nine hundred ninety-seven million, five hundred forty-nine thousand, one hundred twenty-one".