1281897 has 6 divisors (see below), whose sum is σ = 1851642. Its totient is φ = 854592.

The previous prime is 1281883. The next prime is 1281899. The reversal of 1281897 is 7981821.

It can be written as a sum of positive squares in only one way, i.e., 1212201 + 69696 = 1101^2 + 264^2 .

It is a de Polignac number, because none of the positive numbers 2^k-1281897 is a prime.

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (1281899) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 71208 + ... + 71225.

It is an arithmetic number, because the mean of its divisors is an integer number (308607).

2^1281897 is an apocalyptic number.

It is an amenable number.

1281897 is a deficient number, since it is larger than the sum of its proper divisors (569745).

1281897 is a wasteful number, since it uses less digits than its factorization.

1281897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 142439 (or 142436 counting only the distinct ones).

The product of its digits is 8064, while the sum is 36.

The square root of 1281897 is about 1132.2089029857. The cubic root of 1281897 is about 108.6303162110.

It can be divided in two parts, 128 and 1897, that added together give a square (2025 = 45²).

The spelling of 1281897 in words is "one million, two hundred eighty-one thousand, eight hundred ninety-seven".