165539970 has 192 divisors, whose sum is σ = 493718400. Its totient is φ = 39346560.

The previous prime is 165539963. The next prime is 165539971. The reversal of 165539970 is 79935561.

165539970 is a `hidden beast` number, since 1 + 6 + 553 + 9 + 97 + 0 = 666.

165539970 is digitally balanced in base 2, 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 Curzon number.

It is not an unprimeable number, because it can be changed into a prime (165539971) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 2713740 + ... + 2713800.

It is an arithmetic number, because the mean of its divisors is an integer number (2571450).

Almost surely, 2^165539970 is an apocalyptic number.

165539970 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 165539970, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (246859200).

165539970 is an abundant number, since it is smaller than the sum of its proper divisors (328178430).

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

165539970 is a wasteful number, since it uses less digits than its factorization.

165539970 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 142 (or 113 counting only the distinct ones).

The product of its (nonzero) digits is 255150, while the sum is 45.

The square root of 165539970 is about 12866.2337146501. The cubic root of 165539970 is about 549.0783130542.

The spelling of 165539970 in words is "one hundred sixty-five million, five hundred thirty-nine thousand, nine hundred seventy".