165120506 has 4 divisors (see below), whose sum is σ = 247680762. Its totient is φ = 82560252.

The previous prime is 165120499. The next prime is 165120509. The reversal of 165120506 is 605021561.

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

It can be written as a sum of positive squares in only one way, i.e., 162690025 + 2430481 = 12755^2 + 1559^2 .

It is not an unprimeable number, because it can be changed into a prime (165120509) 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 as a sum of consecutive naturals, namely, 41280125 + ... + 41280128.

Almost surely, 2^165120506 is an apocalyptic number.

165120506 is a deficient number, since it is larger than the sum of its proper divisors (82560256).

165120506 is an equidigital number, since it uses as much as digits as its factorization.

165120506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82560255.

The product of its (nonzero) digits is 1800, while the sum is 26.

The square root of 165120506 is about 12849.9224122171. The cubic root of 165120506 is about 548.6141484265.

The spelling of 165120506 in words is "one hundred sixty-five million, one hundred twenty thousand, five hundred six".