165139050661 has 4 divisors (see below), whose sum is σ = 177842054572. Its totient is φ = 152436046752.

The previous prime is 165139050653. The next prime is 165139050683. The reversal of 165139050661 is 166050931561.

165139050661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 166050931561 = 41 ⋅4050022721.

It can be written as a sum of positive squares in 2 ways, for example, as 92619792225 + 72519258436 = 304335^2 + 269294^2 .

It is a cyclic number.

It is not a de Polignac number, because 165139050661 - 2³ = 165139050653 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165139050361) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 6351501936 + ... + 6351501961.

It is an arithmetic number, because the mean of its divisors is an integer number (44460513643).

Almost surely, 2^165139050661 is an apocalyptic number.

It is an amenable number.

165139050661 is a deficient number, since it is larger than the sum of its proper divisors (12703003911).

165139050661 is a wasteful number, since it uses less digits than its factorization.

165139050661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12703003910.

The product of its (nonzero) digits is 145800, while the sum is 43.

The spelling of 165139050661 in words is "one hundred sixty-five billion, one hundred thirty-nine million, fifty thousand, six hundred sixty-one".