164259611521 has 4 divisors (see below), whose sum is σ = 164407727700. Its totient is φ = 164111495344.

The previous prime is 164259611501. The next prime is 164259611597. The reversal of 164259611521 is 125116952461.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 73164299121 + 91095312400 = 270489^2 + 301820^2 .

It is a cyclic number.

It is not a de Polignac number, because 164259611521 - 2⁵ = 164259611489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (164259611501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 74056426 + ... + 74058643.

It is an arithmetic number, because the mean of its divisors is an integer number (41101931925).

Almost surely, 2^164259611521 is an apocalyptic number.

It is an amenable number.

164259611521 is a deficient number, since it is larger than the sum of its proper divisors (148116179).

164259611521 is a wasteful number, since it uses less digits than its factorization.

164259611521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148116178.

The product of its digits is 129600, while the sum is 43.

The spelling of 164259611521 in words is "one hundred sixty-four billion, two hundred fifty-nine million, six hundred eleven thousand, five hundred twenty-one".