1297987 has 4 divisors (see below), whose sum is σ = 1301760. Its totient is φ = 1294216.

The previous prime is 1297979. The next prime is 1297993. The reversal of 1297987 is 7897921.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7897921 = 1049 ⋅7529.

It is a cyclic number.

It is not a de Polignac number, because 1297987 - 2³ = 1297979 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1297927) 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 3 ways as a sum of consecutive naturals, for example, 1312 + ... + 2077.

It is an arithmetic number, because the mean of its divisors is an integer number (325440).

2^1297987 is an apocalyptic number.

1297987 is a deficient number, since it is larger than the sum of its proper divisors (3773).

1297987 is an equidigital number, since it uses as much as digits as its factorization.

1297987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3772.

The product of its digits is 63504, while the sum is 43.

The square root of 1297987 is about 1139.2923242083. The cubic root of 1297987 is about 109.0829265413.

The spelling of 1297987 in words is "one million, two hundred ninety-seven thousand, nine hundred eighty-seven".