1287173 has 2 divisors, whose sum is σ = 1287174.
Its totient is φ = 1287172.
The previous prime is 1287163. The next prime is 1287179. The reversal of 1287173 is 3717821.
It is a strong prime.
It can be written as a sum of positive squares in only one way, i.e., 1249924 + 37249 = 1118^2 + 193^2
It is an emirp because it is prime and its reverse (3717821) is a distict prime.
It is a cyclic number.
It is not a de Polignac number, because 1287173 - 24 = 1287157 is a prime.
It is an Ulam number.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (1287179) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 643586 + 643587.
It is an arithmetic number, because the mean of its divisors is an integer number (643587).
21287173 is an apocalyptic number.
It is an amenable number.
1287173 is a deficient number, since it is larger than the sum of its proper divisors (1).
1287173 is an equidigital number, since it uses as much as digits as its factorization.
1287173 is an evil number, because the sum of its binary digits is even.
The product of its digits is 2352, while the sum is 29.
The square root of 1287173 is about 1134.5364692243.
The cubic root of 1287173 is about 108.7791448727.
Subtracting from 1287173 its product of digits (2352), we obtain a palindrome (1284821).
The spelling of 1287173 in words is "one million, two hundred eighty-seven thousand, one hundred seventy-three".