999971 has 8 divisors (see below), whose sum is σ = 1192704. Its totient is φ = 819720.

The previous prime is 999961. The next prime is 999979. The reversal of 999971 is 179999.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 999971 - 2⁶ = 999907 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 10.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 999971.

It is not an unprimeable number, because it can be changed into a prime (999979) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2945 + ... + 3266.

It is an arithmetic number, because the mean of its divisors is an integer number (149088).

2⁹⁹⁹⁹⁷¹ is an apocalyptic number.

999971 is a deficient number, since it is larger than the sum of its proper divisors (192733).

999971 is a wasteful number, since it uses less digits than its factorization.

999971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6241.

The product of its digits is 45927, while the sum is 44.

The square root of 999971 is about 999.9854998949. The cubic root of 999971 is about 99.9990333240. Note that the first 3 decimals are identical.

The spelling of 999971 in words is "nine hundred ninety-nine thousand, nine hundred seventy-one".