1216324489 has 2 divisors, whose sum is σ = 1216324490. Its totient is φ = 1216324488.

The previous prime is 1216324469. The next prime is 1216324493. The reversal of 1216324489 is 9844236121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1195776400 + 20548089 = 34580^2 + 4533^2 .

It is a cyclic number.

It is not a de Polignac number, because 1216324489 - 2⁵ = 1216324457 is a prime.

It is a super-2 number, since 2×1216324489² = 2958890525082222242, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1216324469) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 608162244 + 608162245.

It is an arithmetic number, because the mean of its divisors is an integer number (608162245).

Almost surely, 2^1216324489 is an apocalyptic number.

It is an amenable number.

1216324489 is a deficient number, since it is larger than the sum of its proper divisors (1).

1216324489 is an equidigital number, since it uses as much as digits as its factorization.

1216324489 is an evil number, because the sum of its binary digits is even.

The product of its digits is 82944, while the sum is 40.

The square root of 1216324489 is about 34875.8439181047. The cubic root of 1216324489 is about 1067.4555926001.

The spelling of 1216324489 in words is "one billion, two hundred sixteen million, three hundred twenty-four thousand, four hundred eighty-nine".