999949 has 8 divisors (see below), whose sum is σ = 1060920. Its totient is φ = 941920.

The previous prime is 999931. The next prime is 999953. The reversal of 999949 is 949999.

It can be written as a sum of positive squares in 4 ways, for example, as 59049 + 940900 = 243^2 + 970^2 .

It is not a de Polignac number, because 999949 - 2⁵ = 999917 is a prime.

It is a Duffinian number.

999949 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999959) 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, 24369 + ... + 24409.

It is an arithmetic number, because the mean of its divisors is an integer number (132615).

2⁹⁹⁹⁹⁴⁹ is an apocalyptic number.

It is an amenable number.

999949 is a deficient number, since it is larger than the sum of its proper divisors (60971).

999949 is an frugal number, since it uses more digits than its factorization.

999949 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128 (or 70 counting only the distinct ones).

The product of its digits is 236196, while the sum is 49.

The square root of 999949 is about 999.9744996749. The cubic root of 999949 is about 99.9982999711.

The spelling of 999949 in words is "nine hundred ninety-nine thousand, nine hundred forty-nine".