1216712121671 has 8 divisors (see below), whose sum is σ = 1234952469504. Its totient is φ = 1198474140600.

The previous prime is 1216712121643. The next prime is 1216712121673. The reversal of 1216712121671 is 1761212176121.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1216712121671 is a prime.

It is a super-2 number, since 2×1216712121671² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216712121673) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 458036 + ... + 1625798.

It is an arithmetic number, because the mean of its divisors is an integer number (154369058688).

Almost surely, 2^{1216712121671} is an apocalyptic number.

1216712121671 is a deficient number, since it is larger than the sum of its proper divisors (18240347833).

1216712121671 is a wasteful number, since it uses less digits than its factorization.

1216712121671 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1183381.

The product of its digits is 14112, while the sum is 38.

Adding to 1216712121671 its reverse (1761212176121), we get a palindrome (2977924297792).

The spelling of 1216712121671 in words is "one trillion, two hundred sixteen billion, seven hundred twelve million, one hundred twenty-one thousand, six hundred seventy-one".