1216185079 has 16 divisors (see below), whose sum is σ = 1318828000. Its totient is φ = 1117597824.

The previous prime is 1216185073. The next prime is 1216185107. The reversal of 1216185079 is 9705816121.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 1216185079 - 2⁷ = 1216184951 is a prime.

It is a super-2 number, since 2×1216185079² = 2958212292764472482, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216185073) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 242869 + ... + 247825.

It is an arithmetic number, because the mean of its divisors is an integer number (82426750).

Almost surely, 2^1216185079 is an apocalyptic number.

1216185079 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

1216185079 is a deficient number, since it is larger than the sum of its proper divisors (102642921).

1216185079 is a wasteful number, since it uses less digits than its factorization.

1216185079 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5362.

The product of its (nonzero) digits is 30240, while the sum is 40.

The square root of 1216185079 is about 34873.8451995188. The cubic root of 1216185079 is about 1067.4148086176.

The spelling of 1216185079 in words is "one billion, two hundred sixteen million, one hundred eighty-five thousand, seventy-nine".