1280357 has 8 divisors (see below), whose sum is σ = 1390200. Its totient is φ = 1172160.

The previous prime is 1280333. The next prime is 1280371. The reversal of 1280357 is 7530821.

It can be written as a sum of positive squares in 4 ways, for example, as 23716 + 1256641 = 154^2 + 1121^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1280357 - 2⁸ = 1280101 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1280317) 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, 1607 + ... + 2267.

It is an arithmetic number, because the mean of its divisors is an integer number (173775).

2^1280357 is an apocalyptic number.

It is an amenable number.

1280357 is a deficient number, since it is larger than the sum of its proper divisors (109843).

1280357 is a wasteful number, since it uses less digits than its factorization.

1280357 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 823.

The product of its (nonzero) digits is 1680, while the sum is 26.

The square root of 1280357 is about 1131.5286120996. The cubic root of 1280357 is about 108.5867979660.

The spelling of 1280357 in words is "one million, two hundred eighty thousand, three hundred fifty-seven".