165405346722001 has 9 divisors (see below), whose sum is σ = 170913532982409. Its totient is φ = 160069304546100.

The previous prime is 165405346721983. The next prime is 165405346722059. The reversal of 165405346722001 is 100227643504561.

The square root of 165405346722001 is 12861001.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 165405346722001 - 2⁵ = 165405346721969 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165405346720001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 398483596 + ... + 398898466.

It is an arithmetic number, because the mean of its divisors is an integer number (18990392553601).

Almost surely, 2^{165405346722001} is an apocalyptic number.

165405346722001 is the 12861001-st square number.

165405346722001 is the 6430501-st centered octagonal number.

It is an amenable number.

165405346722001 is a deficient number, since it is larger than the sum of its proper divisors (5508186260408).

165405346722001 is an frugal number, since it uses more digits than its factorization.

165405346722001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 829804 (or 414902 counting only the distinct ones).

The product of its (nonzero) digits is 1209600, while the sum is 46.

The spelling of 165405346722001 in words is "one hundred sixty-five trillion, four hundred five billion, three hundred forty-six million, seven hundred twenty-two thousand, one".