1251280 has 20 divisors (see below), whose sum is σ = 2909412. Its totient is φ = 500480.

The previous prime is 1251259. The next prime is 1251287. The reversal of 1251280 is 821521.

It can be written as a sum of positive squares in 2 ways, for example, as 968256 + 283024 = 984^2 + 532^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1251287) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7741 + ... + 7900.

2^1251280 is an apocalyptic number.

1251280 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1251280 is an abundant number, since it is smaller than the sum of its proper divisors (1658132).

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

1251280 is a wasteful number, since it uses less digits than its factorization.

1251280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15654 (or 15648 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 19.

The square root of 1251280 is about 1118.6062756842. The cubic root of 1251280 is about 107.7584909769.

It can be divided in two parts, 125 and 1280, that multiplied together give a 4-th power (160000 = 20⁴).

The spelling of 1251280 in words is "one million, two hundred fifty-one thousand, two hundred eighty".