165721079135 has 8 divisors (see below), whose sum is σ = 198874947600. Its totient is φ = 132570428224.

The previous prime is 165721079119. The next prime is 165721079143. The reversal of 165721079135 is 531970127561.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 165721079135 - 2⁴ = 165721079119 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 165721079135.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 689585 + ... + 898314.

It is an arithmetic number, because the mean of its divisors is an integer number (24859368450).

Almost surely, 2^165721079135 is an apocalyptic number.

165721079135 is a deficient number, since it is larger than the sum of its proper divisors (33153868465).

165721079135 is a wasteful number, since it uses less digits than its factorization.

165721079135 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1608777.

The product of its (nonzero) digits is 396900, while the sum is 47.

The spelling of 165721079135 in words is "one hundred sixty-five billion, seven hundred twenty-one million, seventy-nine thousand, one hundred thirty-five".