165220505 has 8 divisors (see below), whose sum is σ = 198474624. Its totient is φ = 132036400.

The previous prime is 165220481. The next prime is 165220507. The reversal of 165220505 is 505022561.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 165220505 - 2⁶ = 165220441 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165220507) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12161 + ... + 21870.

It is an arithmetic number, because the mean of its divisors is an integer number (24809328).

Almost surely, 2^165220505 is an apocalyptic number.

It is an amenable number.

165220505 is a deficient number, since it is larger than the sum of its proper divisors (33254119).

165220505 is an equidigital number, since it uses as much as digits as its factorization.

165220505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35007.

The product of its (nonzero) digits is 3000, while the sum is 26.

The square root of 165220505 is about 12853.8128584479. The cubic root of 165220505 is about 548.7248752254.

The spelling of 165220505 in words is "one hundred sixty-five million, two hundred twenty thousand, five hundred five".