217433980729 has 16 divisors (see below), whose sum is σ = 254740000768. Its totient is φ = 181704820752.

The previous prime is 217433980679. The next prime is 217433980733. The reversal of 217433980729 is 927089334712.

It is a happy number.

It is not a de Polignac number, because 217433980729 - 2²⁹ = 216897109817 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 217433980729.

It is not an unprimeable number, because it can be changed into a prime (217433980739) 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, 495657 + ... + 824950.

It is an arithmetic number, because the mean of its divisors is an integer number (15921250048).

Almost surely, 2^217433980729 is an apocalyptic number.

It is an amenable number.

217433980729 is a deficient number, since it is larger than the sum of its proper divisors (37306020039).

217433980729 is a wasteful number, since it uses less digits than its factorization.

217433980729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1321204.

The product of its (nonzero) digits is 4572288, while the sum is 55.

The spelling of 217433980729 in words is "two hundred seventeen billion, four hundred thirty-three million, nine hundred eighty thousand, seven hundred twenty-nine".