1216611671 has 8 divisors (see below), whose sum is σ = 1336122000. Its totient is φ = 1098586240.

The previous prime is 1216611653. The next prime is 1216611679. The reversal of 1216611671 is 1761166121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1216611671 - 2²⁶ = 1149502807 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216611679) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 369506 + ... + 372783.

It is an arithmetic number, because the mean of its divisors is an integer number (167015250).

Almost surely, 2^1216611671 is an apocalyptic number.

1216611671 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1216611671 is a deficient number, since it is larger than the sum of its proper divisors (119510329).

1216611671 is a wasteful number, since it uses less digits than its factorization.

1216611671 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 742449.

The product of its digits is 3024, while the sum is 32.

The square root of 1216611671 is about 34879.9608801386. The cubic root of 1216611671 is about 1067.5395970226.

Adding to 1216611671 its reverse (1761166121), we get a palindrome (2977777792).

The spelling of 1216611671 in words is "one billion, two hundred sixteen million, six hundred eleven thousand, six hundred seventy-one".