1216683905478 has 16 divisors (see below), whose sum is σ = 2489957760576. Its totient is φ = 396129643560.

The previous prime is 1216683905477. The next prime is 1216683905509. The reversal of 1216683905478 is 8745093866121.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216683905471) 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, 2357914288 + ... + 2357914803.

It is an arithmetic number, because the mean of its divisors is an integer number (155622360036).

It is a 2-persistent number, because it is pandigital, and so is 2⋅1216683905478 = 2433367810956, but 3⋅1216683905478 = 3650051716434 is not.

Almost surely, 2^{1216683905478} is an apocalyptic number.

1216683905478 is an abundant number, since it is smaller than the sum of its proper divisors (1273273855098).

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

1216683905478 is a wasteful number, since it uses less digits than its factorization.

1216683905478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4715829139.

The product of its (nonzero) digits is 17418240, while the sum is 60.

The spelling of 1216683905478 in words is "one trillion, two hundred sixteen billion, six hundred eighty-three million, nine hundred five thousand, four hundred seventy-eight".