33686668538721 has 16 divisors (see below), whose sum is σ = 54443100669120. Its totient is φ = 20416162750560.

The previous prime is 33686668538717. The next prime is 33686668538737. The reversal of 33686668538721 is 12783586668633.

It is not a de Polignac number, because 33686668538721 - 2² = 33686668538717 is a prime.

It is a super-2 number, since 2×33686668538721² (a number of 28 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 33686668538721.

It is not an unprimeable number, because it can be changed into a prime (33686668518721) 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, 56711562900 + ... + 56711563493.

It is an arithmetic number, because the mean of its divisors is an integer number (3402693791820).

Almost surely, 2^{33686668538721} is an apocalyptic number.

It is an amenable number.

33686668538721 is a deficient number, since it is larger than the sum of its proper divisors (20756432130399).

33686668538721 is a wasteful number, since it uses less digits than its factorization.

33686668538721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113423126413 (or 113423126407 counting only the distinct ones).

The product of its digits is 1254113280, while the sum is 72.

The spelling of 33686668538721 in words is "thirty-three trillion, six hundred eighty-six billion, six hundred sixty-eight million, five hundred thirty-eight thousand, seven hundred twenty-one".