165661146 has 64 divisors (see below), whose sum is σ = 428716800. Its totient is φ = 46433088.

The previous prime is 165661127. The next prime is 165661147. The reversal of 165661146 is 641166561.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 165661146.

It is not an unprimeable number, because it can be changed into a prime (165661147) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 15900 + ... + 24168.

It is an arithmetic number, because the mean of its divisors is an integer number (6698700).

Almost surely, 2^165661146 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 165661146, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (214358400).

165661146 is an abundant number, since it is smaller than the sum of its proper divisors (263055654).

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

165661146 is a wasteful number, since it uses less digits than its factorization.

165661146 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8340 (or 8334 counting only the distinct ones).

The product of its digits is 25920, while the sum is 36.

The square root of 165661146 is about 12870.9419235734. The cubic root of 165661146 is about 549.2122563059.

The spelling of 165661146 in words is "one hundred sixty-five million, six hundred sixty-one thousand, one hundred forty-six".