1231985 has 8 divisors (see below), whose sum is σ = 1506600. Its totient is φ = 966784.

The previous prime is 1231981. The next prime is 1231987. The reversal of 1231985 is 5891321.

It can be written as a sum of positive squares in 4 ways, for example, as 579121 + 652864 = 761^2 + 808^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 1231985 - 2² = 1231981 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1231981) 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, 2060 + ... + 2589.

It is an arithmetic number, because the mean of its divisors is an integer number (188325).

2^1231985 is an apocalyptic number.

It is an amenable number.

1231985 is a deficient number, since it is larger than the sum of its proper divisors (274615).

1231985 is an equidigital number, since it uses as much as digits as its factorization.

1231985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4707.

The product of its digits is 2160, while the sum is 29.

The square root of 1231985 is about 1109.9481969894. The cubic root of 1231985 is about 107.2017331438.

The spelling of 1231985 in words is "one million, two hundred thirty-one thousand, nine hundred eighty-five".