997870799128 has 32 divisors (see below), whose sum is σ = 2174536857600. Its totient is φ = 420410456352.

The previous prime is 997870799119. The next prime is 997870799147. The reversal of 997870799128 is 821997078799.

It is a super-2 number, since 2×997870799128² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 151006200 + ... + 151012807.

It is an arithmetic number, because the mean of its divisors is an integer number (67954276800).

Almost surely, 2^997870799128 is an apocalyptic number.

It is an amenable number.

997870799128 is an abundant number, since it is smaller than the sum of its proper divisors (1176666058472).

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

997870799128 is a wasteful number, since it uses less digits than its factorization.

997870799128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 302019079 (or 302019075 counting only the distinct ones).

The product of its (nonzero) digits is 288054144, while the sum is 76.

The spelling of 997870799128 in words is "nine hundred ninety-seven billion, eight hundred seventy million, seven hundred ninety-nine thousand, one hundred twenty-eight".