133681608728 has 8 divisors (see below), whose sum is σ = 250653016380. Its totient is φ = 66840804360.

The previous prime is 133681608727. The next prime is 133681608737. The reversal of 133681608728 is 827806186331.

It is a tau number, because it is divible by the number of its divisors (8).

It is a self number, because there is not a number n which added to its sum of digits gives 133681608728.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133681608727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8355100538 + ... + 8355100553.

Almost surely, 2^133681608728 is an apocalyptic number.

It is an amenable number.

133681608728 is a deficient number, since it is larger than the sum of its proper divisors (116971407652).

133681608728 is a wasteful number, since it uses less digits than its factorization.

133681608728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16710201097 (or 16710201093 counting only the distinct ones).

The product of its (nonzero) digits is 2322432, while the sum is 53.

The spelling of 133681608728 in words is "one hundred thirty-three billion, six hundred eighty-one million, six hundred eight thousand, seven hundred twenty-eight".