997897860 has 144 divisors (see below), whose sum is σ = 3277209600. Its totient is φ = 252051264.

The previous prime is 997897753. The next prime is 997897867. The reversal of 997897860 is 68798799.

It is not an unprimeable number, because it can be changed into a prime (997897867) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 192381 + ... + 197499.

It is an arithmetic number, because the mean of its divisors is an integer number (22758400).

Almost surely, 2^997897860 is an apocalyptic number.

997897860 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 997897860, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1638604800).

997897860 is an abundant number, since it is smaller than the sum of its proper divisors (2279311740).

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

997897860 is a wasteful number, since it uses less digits than its factorization.

997897860 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5175 (or 5148 counting only the distinct ones).

The product of its (nonzero) digits is 13716864, while the sum is 63.

The square root of 997897860 is about 31589.5213638953. The cubic root of 997897860 is about 999.2987950933.

The spelling of 997897860 in words is "nine hundred ninety-seven million, eight hundred ninety-seven thousand, eight hundred sixty".