216685697744446 has 64 divisors (see below), whose sum is σ = 382627819284480. Its totient is φ = 90125262339840.

The previous prime is 216685697744393. The next prime is 216685697744471. The reversal of 216685697744446 is 644447796586612.

It is a Smith number, since the sum of its digits (79) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Harshad number since it is a multiple of its sum of digits (79).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12093186 + ... + 24075226.

It is an arithmetic number, because the mean of its divisors is an integer number (5978559676320).

Almost surely, 2^{216685697744446} is an apocalyptic number.

216685697744446 is a deficient number, since it is larger than the sum of its proper divisors (165942121540034).

216685697744446 is a wasteful number, since it uses less digits than its factorization.

216685697744446 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11982409.

The product of its digits is 11705057280, while the sum is 79.

The spelling of 216685697744446 in words is "two hundred sixteen trillion, six hundred eighty-five billion, six hundred ninety-seven million, seven hundred forty-four thousand, four hundred forty-six".