1216329842 has 54 divisors (see below), whose sum is σ = 2306700909. Its totient is φ = 479409840.

The previous prime is 1216329839. The next prime is 1216329871. The reversal of 1216329842 is 2489236121.

It can be written as a sum of positive squares in 2 ways, for example, as 1039998001 + 176331841 = 32249^2 + 13279^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=24661.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1216329796 and 1216329805.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 4488167 + ... + 4488437.

Almost surely, 2^1216329842 is an apocalyptic number.

1216329842 is a deficient number, since it is larger than the sum of its proper divisors (1090371067).

1216329842 is an equidigital number, since it uses as much as digits as its factorization.

1216329842 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 584 (or 293 counting only the distinct ones).

The product of its digits is 41472, while the sum is 38.

The square root of 1216329842 is about 34875.9206616829. The cubic root of 1216329842 is about 1067.4571585423.

Multiplying 1216329842 by its product of digits (41472), we get a square (50443631207424 = 7102368²).

The spelling of 1216329842 in words is "one billion, two hundred sixteen million, three hundred twenty-nine thousand, eight hundred forty-two".