999397 has 4 divisors (see below), whose sum is σ = 1142176. Its totient is φ = 856620.

The previous prime is 999389. The next prime is 999431. The reversal of 999397 is 793999.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 999397 - 2³ = 999389 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999307) 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, 71379 + ... + 71392.

It is an arithmetic number, because the mean of its divisors is an integer number (285544).

2⁹⁹⁹³⁹⁷ is an apocalyptic number.

It is an amenable number.

999397 is a deficient number, since it is larger than the sum of its proper divisors (142779).

999397 is a wasteful number, since it uses less digits than its factorization.

999397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142778.

The product of its digits is 137781, while the sum is 46.

The square root of 999397 is about 999.6984545352. The cubic root of 999397 is about 99.9798959585.

The spelling of 999397 in words is "nine hundred ninety-nine thousand, three hundred ninety-seven".