165655980 has 144 divisors (see below), whose sum is σ = 582464064. Its totient is φ = 37324800.

The previous prime is 165655961. The next prime is 165655981. The reversal of 165655980 is 89556561.

It is a happy number.

165655980 is a `hidden beast` number, since 1 + 6 + 56 + 5 + 598 + 0 = 666.

165655980 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165655981) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 91080 + ... + 92880.

Almost surely, 2^165655980 is an apocalyptic number.

165655980 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 165655980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (291232032).

165655980 is an abundant number, since it is smaller than the sum of its proper divisors (416808084).

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

165655980 is a wasteful number, since it uses less digits than its factorization.

165655980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1896 (or 1891 counting only the distinct ones).

The product of its (nonzero) digits is 324000, while the sum is 45.

The square root of 165655980 is about 12870.7412373958. The cubic root of 165655980 is about 549.2065473430.

The spelling of 165655980 in words is "one hundred sixty-five million, six hundred fifty-five thousand, nine hundred eighty".