165921198655 has 8 divisors (see below), whose sum is σ = 199123093584. Its totient is φ = 132725188800.

The previous prime is 165921198649. The next prime is 165921198679. The reversal of 165921198655 is 556891129561.

165921198655 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 165921198655 - 2¹¹ = 165921196607 is a prime.

It is a super-2 number, since 2×165921198655² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 165921198655.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1409001 + ... + 1522210.

It is an arithmetic number, because the mean of its divisors is an integer number (24890386698).

Almost surely, 2^165921198655 is an apocalyptic number.

165921198655 is a deficient number, since it is larger than the sum of its proper divisors (33201894929).

165921198655 is a wasteful number, since it uses less digits than its factorization.

165921198655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2942537.

The product of its digits is 5832000, while the sum is 58.

The spelling of 165921198655 in words is "one hundred sixty-five billion, nine hundred twenty-one million, one hundred ninety-eight thousand, six hundred fifty-five".