1287965 has 16 divisors (see below), whose sum is σ = 1804800. Its totient is φ = 882000.

The previous prime is 1287961. The next prime is 1287967. The reversal of 1287965 is 5697821.

It is not a de Polignac number, because 1287965 - 2² = 1287961 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1287961) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1340 + ... + 2090.

It is an arithmetic number, because the mean of its divisors is an integer number (112800).

2^1287965 is an apocalyptic number.

It is an amenable number.

1287965 is a deficient number, since it is larger than the sum of its proper divisors (516835).

1287965 is an frugal number, since it uses more digits than its factorization.

1287965 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 777 (or 763 counting only the distinct ones).

The product of its digits is 30240, while the sum is 38.

The square root of 1287965 is about 1134.8854567753. The cubic root of 1287965 is about 108.8014509701.

The spelling of 1287965 in words is "one million, two hundred eighty-seven thousand, nine hundred sixty-five".