997738992 has 80 divisors (see below), whose sum is σ = 2917982880. Its totient is φ = 326297088.

The previous prime is 997738991. The next prime is 997739033. The reversal of 997738992 is 299837799.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (997738991) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1108 + ... + 44684.

It is an arithmetic number, because the mean of its divisors is an integer number (36474786).

Almost surely, 2^997738992 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 997738992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1458991440).

997738992 is an abundant number, since it is smaller than the sum of its proper divisors (1920243888).

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

997738992 is a wasteful number, since it uses less digits than its factorization.

997738992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43647 (or 43635 counting only the distinct ones).

The product of its digits is 15431472, while the sum is 63.

The square root of 997738992 is about 31587.0066957919. The cubic root of 997738992 is about 999.2457619346.

The spelling of 997738992 in words is "nine hundred ninety-seven million, seven hundred thirty-eight thousand, nine hundred ninety-two".