165145661506645 has 4 divisors (see below), whose sum is σ = 198174793807980. Its totient is φ = 132116529205312.

The previous prime is 165145661506613. The next prime is 165145661506663. The reversal of 165145661506645 is 546605166541561.

165145661506645 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.

It can be written as a sum of positive squares in 2 ways, for example, as 103020084314161 + 62125577192484 = 10149881^2 + 7881978^2 .

It is a cyclic number.

It is not a de Polignac number, because 165145661506645 - 2⁵ = 165145661506613 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16514566150660 + ... + 16514566150669.

It is an arithmetic number, because the mean of its divisors is an integer number (49543698451995).

Almost surely, 2^{165145661506645} is an apocalyptic number.

It is an amenable number.

165145661506645 is a deficient number, since it is larger than the sum of its proper divisors (33029132301335).

165145661506645 is an equidigital number, since it uses as much as digits as its factorization.

165145661506645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33029132301334.

The product of its (nonzero) digits is 77760000, while the sum is 61.

The spelling of 165145661506645 in words is "one hundred sixty-five trillion, one hundred forty-five billion, six hundred sixty-one million, five hundred six thousand, six hundred forty-five".