165161506 has 4 divisors (see below), whose sum is σ = 247742262. Its totient is φ = 82580752.

The previous prime is 165161461. The next prime is 165161519. The reversal of 165161506 is 605161561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 605161561 = 3407 ⋅177623.

It can be written as a sum of positive squares in only one way, i.e., 141395881 + 23765625 = 11891^2 + 4875^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41290375 + ... + 41290378.

Almost surely, 2^165161506 is an apocalyptic number.

165161506 is a deficient number, since it is larger than the sum of its proper divisors (82580756).

165161506 is an equidigital number, since it uses as much as digits as its factorization.

165161506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82580755.

The product of its (nonzero) digits is 5400, while the sum is 31.

The square root of 165161506 is about 12851.5176535692. The cubic root of 165161506 is about 548.6595522737.

The spelling of 165161506 in words is "one hundred sixty-five million, one hundred sixty-one thousand, five hundred six".