1243940 has 36 divisors (see below), whose sum is σ = 2749908. Its totient is φ = 472320.

The previous prime is 1243939. The next prime is 1243943. The reversal of 1243940 is 493421.

It can be written as a sum of positive squares in 6 ways, for example, as 195364 + 1048576 = 442^2 + 1024^2 .

It is not an unprimeable number, because it can be changed into a prime (1243943) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 30320 + ... + 30360.

2^1243940 is an apocalyptic number.

1243940 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1243940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1374954).

1243940 is an abundant number, since it is smaller than the sum of its proper divisors (1505968).

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

1243940 is a wasteful number, since it uses less digits than its factorization.

1243940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128 (or 85 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 1243940 is about 1115.3205817163. The cubic root of 1243940 is about 107.5473741079.

The spelling of 1243940 in words is "one million, two hundred forty-three thousand, nine hundred forty".