165143821608 has 96 divisors (see below), whose sum is σ = 458531073000. Its totient is φ = 53663385600.

The previous prime is 165143821607. The next prime is 165143821627. The reversal of 165143821608 is 806128341561.

165143821608 is a `hidden beast` number, since 1 + 6 + 5 + 1 + 4 + 38 + 2 + 1 + 608 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 162972075204 + 2171746404 = 403698^2 + 46602^2 .

It is not an unprimeable number, because it can be changed into a prime (165143821607) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3878418 + ... + 3920766.

Almost surely, 2^165143821608 is an apocalyptic number.

165143821608 is a gapful number since it is divisible by the number (18) 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 165143821608, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (229265536500).

165143821608 is an abundant number, since it is smaller than the sum of its proper divisors (293387251392).

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

165143821608 is a wasteful number, since it uses less digits than its factorization.

165143821608 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43723 (or 43716 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 45.

The spelling of 165143821608 in words is "one hundred sixty-five billion, one hundred forty-three million, eight hundred twenty-one thousand, six hundred eight".