1216999 has 8 divisors (see below), whose sum is σ = 1451520. Its totient is φ = 997656.

The previous prime is 1216997. The next prime is 1217009. The reversal of 1216999 is 9996121.

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 1216999 - 2¹ = 1216997 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216997) 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 7 ways as a sum of consecutive naturals, for example, 3619 + ... + 3940.

It is an arithmetic number, because the mean of its divisors is an integer number (181440).

2^1216999 is an apocalyptic number.

1216999 is a deficient number, since it is larger than the sum of its proper divisors (234521).

1216999 is an equidigital number, since it uses as much as digits as its factorization.

1216999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7589.

The product of its digits is 8748, while the sum is 37.

The square root of 1216999 is about 1103.1767764053. The cubic root of 1216999 is about 106.7652874793.

The spelling of 1216999 in words is "one million, two hundred sixteen thousand, nine hundred ninety-nine".