1216660056 has 32 divisors (see below), whose sum is σ = 3042800640. Its totient is φ = 405399968.

The previous prime is 1216660051. The next prime is 1216660057. The reversal of 1216660056 is 6500666121.

It is a junction number, because it is equal to n+sod(n) for n = 1216659999 and 1216660026.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216660051) 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, 68005 + ... + 84011.

It is an arithmetic number, because the mean of its divisors is an integer number (95087520).

Almost surely, 2^1216660056 is an apocalyptic number.

It is an amenable number.

1216660056 is an abundant number, since it is smaller than the sum of its proper divisors (1826140584).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1216660056 is a wasteful number, since it uses less digits than its factorization.

1216660056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19183 (or 19179 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 33.

The square root of 1216660056 is about 34880.6544663371. The cubic root of 1216660056 is about 1067.5537489551.

The spelling of 1216660056 in words is "one billion, two hundred sixteen million, six hundred sixty thousand, fifty-six".