997891384 has 16 divisors (see below), whose sum is σ = 2138338800. Its totient is φ = 427667712.

The previous prime is 997891337. The next prime is 997891387. The reversal of 997891384 is 483198799.

It is a happy number.

It is a super-3 number, since 3×997891384³ (a number of 28 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (997891387) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8909689 + ... + 8909800.

It is an arithmetic number, because the mean of its divisors is an integer number (133646175).

Almost surely, 2^997891384 is an apocalyptic number.

It is an amenable number.

997891384 is an abundant number, since it is smaller than the sum of its proper divisors (1140447416).

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

997891384 is a wasteful number, since it uses less digits than its factorization.

997891384 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17819502 (or 17819498 counting only the distinct ones).

The product of its digits is 3919104, while the sum is 58.

The square root of 997891384 is about 31589.4188613846. The cubic root of 997891384 is about 999.2966333914.

The spelling of 997891384 in words is "nine hundred ninety-seven million, eight hundred ninety-one thousand, three hundred eighty-four".