1245 has 8 divisors (see below), whose sum is σ = 2016. Its totient is φ = 656.

The previous prime is 1237. The next prime is 1249. The reversal of 1245 is 5421.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1245 - 2³ = 1237 is a prime.

1245 is a lucky number.

It is a plaindrome in base 8, base 10 and base 16.

It is a nialpdrome in base 6 and base 11.

It is a self number, because there is not a number n which added to its sum of digits gives 1245.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1249) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27 + ... + 56.

It is an arithmetic number, because the mean of its divisors is an integer number (252).

2¹²⁴⁵ is an apocalyptic number.

1245 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1245 is a deficient number, since it is larger than the sum of its proper divisors (771).

1245 is an equidigital number, since it uses as much as digits as its factorization.

1245 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91.

The product of its digits is 40, while the sum is 12.

The square root of 1245 is about 35.2845575288. The cubic root of 1245 is about 10.7577913590.

Adding to 1245 its reverse (5421), we get a palindrome (6666).

The spelling of 1245 in words is "one thousand, two hundred forty-five".