217436861939 has 12 divisors (see below), whose sum is σ = 242026186080. Its totient is φ = 195167715600.

The previous prime is 217436861909. The next prime is 217436861959. The reversal of 217436861939 is 939168634712.

It is not a de Polignac number, because 217436861939 - 2¹² = 217436857843 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (217436861909) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11363852 + ... + 11382969.

It is an arithmetic number, because the mean of its divisors is an integer number (20168848840).

Almost surely, 2^217436861939 is an apocalyptic number.

217436861939 is a deficient number, since it is larger than the sum of its proper divisors (24589324141).

217436861939 is a wasteful number, since it uses less digits than its factorization.

217436861939 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22746922 (or 22746911 counting only the distinct ones).

The product of its digits is 11757312, while the sum is 59.

The spelling of 217436861939 in words is "two hundred seventeen billion, four hundred thirty-six million, eight hundred sixty-one thousand, nine hundred thirty-nine".