1247920 has 40 divisors (see below), whose sum is σ = 3057840. Its totient is φ = 472320.

The previous prime is 1247893. The next prime is 1247923. The reversal of 1247920 is 297421.

It is a tau number, because it is divible by the number of its divisors (40).

It is not an unprimeable number, because it can be changed into a prime (1247923) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1110 + ... + 1930.

It is an arithmetic number, because the mean of its divisors is an integer number (76446).

2^1247920 is an apocalyptic number.

1247920 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 1247920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1528920).

1247920 is an abundant number, since it is smaller than the sum of its proper divisors (1809920).

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

1247920 is a wasteful number, since it uses less digits than its factorization.

1247920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 853 (or 847 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 25.

The square root of 1247920 is about 1117.1033971840. The cubic root of 1247920 is about 107.6619516744.

The spelling of 1247920 in words is "one million, two hundred forty-seven thousand, nine hundred twenty".