217780944411 has 16 divisors (see below), whose sum is σ = 306925773440. Its totient is φ = 136975121280.

The previous prime is 217780944401. The next prime is 217780944443. The reversal of 217780944411 is 114449087712.

It is a de Polignac number, because none of the positive numbers 2^k-217780944411 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (217780944401) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7913065 + ... + 7940538.

It is an arithmetic number, because the mean of its divisors is an integer number (19182860840).

Almost surely, 2^217780944411 is an apocalyptic number.

217780944411 is a deficient number, since it is larger than the sum of its proper divisors (89144829029).

217780944411 is a wasteful number, since it uses less digits than its factorization.

217780944411 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15853866.

The product of its (nonzero) digits is 451584, while the sum is 48.

The spelling of 217780944411 in words is "two hundred seventeen billion, seven hundred eighty million, nine hundred forty-four thousand, four hundred eleven".