1243904 has 36 divisors (see below), whose sum is σ = 2563176. Its totient is φ = 602112.

The previous prime is 1243889. The next prime is 1243927. The reversal of 1243904 is 4093421.

It is a super-2 number, since 2×1243904² = 3094594322432, which contains 22 as substring.

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 1243904.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10952 + ... + 11064.

2^1243904 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1243904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1281588).

1243904 is an abundant number, since it is smaller than the sum of its proper divisors (1319272).

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

1243904 is an equidigital number, since it uses as much as digits as its factorization.

1243904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 172 (or 158 counting only the distinct ones).

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

The square root of 1243904 is about 1115.3044427420. The cubic root of 1243904 is about 107.5463366134.

The spelling of 1243904 in words is "one million, two hundred forty-three thousand, nine hundred four".