1216705217155 has 16 divisors (see below), whose sum is σ = 1476460665504. Its totient is φ = 962481864960.

The previous prime is 1216705217149. The next prime is 1216705217173. The reversal of 1216705217155 is 5517125076121.

It is not a de Polignac number, because 1216705217155 - 2¹³ = 1216705208963 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3628506 + ... + 3949615.

It is an arithmetic number, because the mean of its divisors is an integer number (92278791594).

Almost surely, 2^{1216705217155} is an apocalyptic number.

1216705217155 is a deficient number, since it is larger than the sum of its proper divisors (259755448349).

1216705217155 is a wasteful number, since it uses less digits than its factorization.

1216705217155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7578486.

The product of its (nonzero) digits is 147000, while the sum is 43.

The spelling of 1216705217155 in words is "one trillion, two hundred sixteen billion, seven hundred five million, two hundred seventeen thousand, one hundred fifty-five".