39986697217 has 4 divisors (see below), whose sum is σ = 39999184560. Its totient is φ = 39974209876.

The previous prime is 39986697187. The next prime is 39986697221. The reversal of 39986697217 is 71279668993.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 39986697217 - 2¹¹ = 39986695169 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (39986697287) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6238867 + ... + 6245272.

It is an arithmetic number, because the mean of its divisors is an integer number (9999796140).

Almost surely, 2^39986697217 is an apocalyptic number.

It is an amenable number.

39986697217 is a deficient number, since it is larger than the sum of its proper divisors (12487343).

39986697217 is a wasteful number, since it uses less digits than its factorization.

39986697217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12487342.

The product of its digits is 61725888, while the sum is 67.

The spelling of 39986697217 in words is "thirty-nine billion, nine hundred eighty-six million, six hundred ninety-seven thousand, two hundred seventeen".