1216447 has 4 divisors (see below), whose sum is σ = 1269360. Its totient is φ = 1163536.

The previous prime is 1216441. The next prime is 1216451. The reversal of 1216447 is 7446121.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1216447 is a prime.

It is an Ulam number.

It is a Duffinian number.

1216447 is a lucky number.

It is a plaindrome in base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216441) 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, 26422 + ... + 26467.

It is an arithmetic number, because the mean of its divisors is an integer number (317340).

2^1216447 is an apocalyptic number.

1216447 is a deficient number, since it is larger than the sum of its proper divisors (52913).

1216447 is an equidigital number, since it uses as much as digits as its factorization.

1216447 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52912.

The product of its digits is 1344, while the sum is 25.

The square root of 1216447 is about 1102.9265614718. The cubic root of 1216447 is about 106.7491430258.

It can be divided in two parts, 121 and 6447, that multiplied together give a palindrome (780087).

The spelling of 1216447 in words is "one million, two hundred sixteen thousand, four hundred forty-seven".