999697 has 4 divisors (see below), whose sum is σ = 1001700. Its totient is φ = 997696.

The previous prime is 999683. The next prime is 999721. The reversal of 999697 is 796999.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 690561 + 309136 = 831^2 + 556^2 .

It is a cyclic number.

It is not a de Polignac number, because 999697 - 2¹¹ = 997649 is a prime.

It is an Ulam number.

It is a Duffinian number.

999697 is a lucky number.

It is a nialpdrome in base 16.

It is a self number, because there is not a number n which added to its sum of digits gives 999697.

It is not an unprimeable number, because it can be changed into a prime (999667) 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, 429 + ... + 1477.

It is an arithmetic number, because the mean of its divisors is an integer number (250425).

2⁹⁹⁹⁶⁹⁷ is an apocalyptic number.

It is an amenable number.

999697 is a deficient number, since it is larger than the sum of its proper divisors (2003).

999697 is a wasteful number, since it uses less digits than its factorization.

999697 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2002.

The product of its digits is 275562, while the sum is 49.

The square root of 999697 is about 999.8484885221. The cubic root of 999697 is about 99.9898989797.

The spelling of 999697 in words is "nine hundred ninety-nine thousand, six hundred ninety-seven".