997738568 has 64 divisors (see below), whose sum is σ = 2033910000. Its totient is φ = 457080832.

The previous prime is 997738561. The next prime is 997738579. The reversal of 997738568 is 865837799.

It is a Cunningham number, because it is equal to 31587²-1.

It can be written as a sum of positive squares in 8 ways, for example, as 234763684 + 762974884 = 15322^2 + 27622^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 997738568.

It is not an unprimeable number, because it can be changed into a prime (997738561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1073528 + ... + 1074456.

Almost surely, 2^997738568 is an apocalyptic number.

It is an amenable number.

997738568 is an abundant number, since it is smaller than the sum of its proper divisors (1036171432).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

997738568 is a wasteful number, since it uses less digits than its factorization.

997738568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1154 (or 1150 counting only the distinct ones).

The product of its digits is 22861440, while the sum is 62.

The square root of 997738568 is about 31586.9999841707. Note that the first 4 decimals coincide. The cubic root of 997738568 is about 999.2456203878.

The spelling of 997738568 in words is "nine hundred ninety-seven million, seven hundred thirty-eight thousand, five hundred sixty-eight".