1247904 has 72 divisors (see below), whose sum is σ = 4062240. Its totient is φ = 355968.

The previous prime is 1247893. The next prime is 1247923. The reversal of 1247904 is 4097421.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (72).

It is an Ulam number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1707 + ... + 2325.

It is an arithmetic number, because the mean of its divisors is an integer number (56420).

2^1247904 is an apocalyptic number.

1247904 is a gapful number since it is divisible by the number (14) 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 1247904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2031120).

1247904 is an abundant number, since it is smaller than the sum of its proper divisors (2814336).

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

1247904 is a wasteful number, since it uses less digits than its factorization.

1247904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 642 (or 631 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 27.

The square root of 1247904 is about 1117.0962357828. The cubic root of 1247904 is about 107.6614915491.

The spelling of 1247904 in words is "one million, two hundred forty-seven thousand, nine hundred four".