1216331117 has 2 divisors, whose sum is σ = 1216331118. Its totient is φ = 1216331116.

The previous prime is 1216331111. The next prime is 1216331177. The reversal of 1216331117 is 7111336121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1156408036 + 59923081 = 34006^2 + 7741^2 .

It is a cyclic number.

It is not a de Polignac number, because 1216331117 - 2⁴ = 1216331101 is a prime.

It is a super-3 number, since 3×1216331117³ (a number of 28 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1216331111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 608165558 + 608165559.

It is an arithmetic number, because the mean of its divisors is an integer number (608165559).

Almost surely, 2^1216331117 is an apocalyptic number.

It is an amenable number.

1216331117 is a deficient number, since it is larger than the sum of its proper divisors (1).

1216331117 is an equidigital number, since it uses as much as digits as its factorization.

1216331117 is an evil number, because the sum of its binary digits is even.

The product of its digits is 756, while the sum is 26.

The square root of 1216331117 is about 34875.9389407655. The cubic root of 1216331117 is about 1067.4575315243.

Adding to 1216331117 its reverse (7111336121), we get a palindrome (8327667238).

The spelling of 1216331117 in words is "one billion, two hundred sixteen million, three hundred thirty-one thousand, one hundred seventeen".