1231644 has 24 divisors (see below), whose sum is σ = 2893968. Its totient is φ = 407680.

The previous prime is 1231631. The next prime is 1231663. The reversal of 1231644 is 4461321.

1231644 is an esthetic number in base 8, because in such base its adjacent digits differ by 1.

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 1231644.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2104 + ... + 2624.

It is an arithmetic number, because the mean of its divisors is an integer number (120582).

2^1231644 is an apocalyptic number.

It is an amenable number.

1231644 is an abundant number, since it is smaller than the sum of its proper divisors (1662324).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1231644 is a wasteful number, since it uses less digits than its factorization.

1231644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 725 (or 723 counting only the distinct ones).

The product of its digits is 576, while the sum is 21.

The square root of 1231644 is about 1109.7945755860. The cubic root of 1231644 is about 107.1918414746.

Adding to 1231644 its sum of digits (21), we get a triangular number (1231665 = T₁₅₆₉).

Adding to 1231644 its reverse (4461321), we get a palindrome (5692965).

The spelling of 1231644 in words is "one million, two hundred thirty-one thousand, six hundred forty-four".