1280745 has 32 divisors (see below), whose sum is σ = 2332800. Its totient is φ = 666432.

The previous prime is 1280743. The next prime is 1280759. The reversal of 1280745 is 5470821.

It is not a de Polignac number, because 1280745 - 2¹ = 1280743 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1280743) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7066 + ... + 7244.

It is an arithmetic number, because the mean of its divisors is an integer number (72900).

2^1280745 is an apocalyptic number.

1280745 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1280745 is a deficient number, since it is larger than the sum of its proper divisors (1052055).

1280745 is a wasteful number, since it uses less digits than its factorization.

1280745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 246 (or 240 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 27.

The square root of 1280745 is about 1131.7000485995. The cubic root of 1280745 is about 108.5977655900.

It can be divided in two parts, 1280 and 745, that added together give a square (2025 = 45²).

The spelling of 1280745 in words is "one million, two hundred eighty thousand, seven hundred forty-five".