9978399 has 6 divisors (see below), whose sum is σ = 14413256. Its totient is φ = 6652260.

The previous prime is 9978383. The next prime is 9978427. The reversal of 9978399 is 9938799.

It is a happy number.

It is not a de Polignac number, because 9978399 - 2⁴ = 9978383 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9978359) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 554347 + ... + 554364.

Almost surely, 2^9978399 is an apocalyptic number.

9978399 is a deficient number, since it is larger than the sum of its proper divisors (4434857).

9978399 is a wasteful number, since it uses less digits than its factorization.

9978399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1108717 (or 1108714 counting only the distinct ones).

The product of its digits is 1102248, while the sum is 54.

The square root of 9978399 is about 3158.8603957757. The cubic root of 9978399 is about 215.2882306936.

The spelling of 9978399 in words is "nine million, nine hundred seventy-eight thousand, three hundred ninety-nine".