1285997 has 4 divisors (see below), whose sum is σ = 1288896. Its totient is φ = 1283100.

The previous prime is 1285993. The next prime is 1286011. The reversal of 1285997 is 7995821.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1285997 - 2² = 1285993 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 (1285993) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 629 + ... + 1722.

It is an arithmetic number, because the mean of its divisors is an integer number (322224).

2^1285997 is an apocalyptic number.

It is an amenable number.

1285997 is a deficient number, since it is larger than the sum of its proper divisors (2899).

1285997 is an equidigital number, since it uses as much as digits as its factorization.

1285997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2898.

The product of its digits is 45360, while the sum is 41.

The square root of 1285997 is about 1134.0180774573. The cubic root of 1285997 is about 108.7460068116.

Subtracting from 1285997 its sum of digits (41), we obtain a square (1285956 = 1134²).

The spelling of 1285997 in words is "one million, two hundred eighty-five thousand, nine hundred ninety-seven".