1281997 has 8 divisors (see below), whose sum is σ = 1350720. Its totient is φ = 1214400.

The previous prime is 1281983. The next prime is 1282007. The reversal of 1281997 is 7991821.

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

It is not a de Polignac number, because 1281997 - 2¹⁹ = 757709 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 (1281937) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2997 + ... + 3397.

It is an arithmetic number, because the mean of its divisors is an integer number (168840).

2^1281997 is an apocalyptic number.

It is an amenable number.

1281997 is a deficient number, since it is larger than the sum of its proper divisors (68723).

1281997 is a wasteful number, since it uses less digits than its factorization.

1281997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 563.

The product of its digits is 9072, while the sum is 37.

The square root of 1281997 is about 1132.2530635861. The cubic root of 1281997 is about 108.6331408657.

It can be divided in two parts, 1281 and 997, that added together give a triangular number (2278 = T₆₇).

The spelling of 1281997 in words is "one million, two hundred eighty-one thousand, nine hundred ninety-seven".