1243638 has 36 divisors (see below), whose sum is σ = 2966964. Its totient is φ = 376200.

The previous prime is 1243631. The next prime is 1243639. The reversal of 1243638 is 8363421.

It is a happy number.

1243638 is a `hidden beast` number, since 1 + 24 + 3 + 638 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1243631) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 1893 + ... + 2463.

2^1243638 is an apocalyptic number.

1243638 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1243638, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1483482).

1243638 is an abundant number, since it is smaller than the sum of its proper divisors (1723326).

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

1243638 is a wasteful number, since it uses less digits than its factorization.

1243638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 601 (or 587 counting only the distinct ones).

The product of its digits is 3456, while the sum is 27.

The square root of 1243638 is about 1115.1851864152. The cubic root of 1243638 is about 107.5386700612.

It can be divided in two parts, 1243 and 638, that added together give a palindrome (1881).

The spelling of 1243638 in words is "one million, two hundred forty-three thousand, six hundred thirty-eight".