165640530 has 48 divisors (see below), whose sum is σ = 436972032. Its totient is φ = 40154400.

The previous prime is 165640511. The next prime is 165640543. The reversal of 165640530 is 35046561.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a Curzon number.

It is a nialpdrome in base 11.

It is an unprimeable number.

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 in 23 ways as a sum of consecutive naturals, for example, 19186 + ... + 26445.

It is an arithmetic number, because the mean of its divisors is an integer number (9103584).

Almost surely, 2^165640530 is an apocalyptic number.

165640530 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

165640530 is an abundant number, since it is smaller than the sum of its proper divisors (271331502).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

165640530 is a wasteful number, since it uses less digits than its factorization.

165640530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45663 (or 45652 counting only the distinct ones).

The product of its (nonzero) digits is 10800, while the sum is 30.

The square root of 165640530 is about 12870.1410248684. The cubic root of 165640530 is about 549.1894727910.

The spelling of 165640530 in words is "one hundred sixty-five million, six hundred forty thousand, five hundred thirty".