165144721075 has 24 divisors (see below), whose sum is σ = 215986176000. Its totient is φ = 124913302560.

The previous prime is 165144721031. The next prime is 165144721081. The reversal of 165144721075 is 570127441561.

It is not a de Polignac number, because 165144721075 - 2¹⁷ = 165144590003 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 106675 + ... + 584524.

It is an arithmetic number, because the mean of its divisors is an integer number (8999424000).

Almost surely, 2^165144721075 is an apocalyptic number.

165144721075 is a deficient number, since it is larger than the sum of its proper divisors (50841454925).

165144721075 is a wasteful number, since it uses less digits than its factorization.

165144721075 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 691731 (or 691726 counting only the distinct ones).

The product of its (nonzero) digits is 235200, while the sum is 43.

The spelling of 165144721075 in words is "one hundred sixty-five billion, one hundred forty-four million, seven hundred twenty-one thousand, seventy-five".