997128880 has 80 divisors (see below), whose sum is σ = 2677891104. Its totient is φ = 341258240.

The previous prime is 997128877. The next prime is 997128887. The reversal of 997128880 is 88821799.

It is a tau number, because it is divible by the number of its divisors (80).

It is not an unprimeable number, because it can be changed into a prime (997128887) 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 in 15 ways as a sum of consecutive naturals, for example, 18367 + ... + 48286.

Almost surely, 2^997128880 is an apocalyptic number.

It is an amenable number.

997128880 is an abundant number, since it is smaller than the sum of its proper divisors (1680762224).

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

997128880 is a wasteful number, since it uses less digits than its factorization.

997128880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66694 (or 66688 counting only the distinct ones).

The product of its (nonzero) digits is 580608, while the sum is 52.

The square root of 997128880 is about 31577.3475770211. The cubic root of 997128880 is about 999.0420426107.

The spelling of 997128880 in words is "nine hundred ninety-seven million, one hundred twenty-eight thousand, eight hundred eighty".