1209831 has 16 divisors (see below), whose sum is σ = 1880064. Its totient is φ = 677664.

The previous prime is 1209821. The next prime is 1209841. The reversal of 1209831 is 1389021.

It is an interprime number because it is at equal distance from previous prime (1209821) and next prime (1209841).

It is a de Polignac number, because none of the positive numbers 2^k-1209831 is a prime.

It is a super-2 number, since 2×1209831² = 2927382097122, which contains 22 as substring.

It is a plaindrome in base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1209811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 570 + ... + 1656.

It is an arithmetic number, because the mean of its divisors is an integer number (117504).

2^1209831 is an apocalyptic number.

1209831 is a deficient number, since it is larger than the sum of its proper divisors (670233).

1209831 is a wasteful number, since it uses less digits than its factorization.

1209831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1150.

The product of its (nonzero) digits is 432, while the sum is 24.

The square root of 1209831 is about 1099.9231791357. The cubic root of 1209831 is about 106.5552623774. Note that the first 3 decimals are identical.

The spelling of 1209831 in words is "one million, two hundred nine thousand, eight hundred thirty-one".