165641598 has 40 divisors (see below), whose sum is σ = 372574488. Its totient is φ = 55003536.

The previous prime is 165641569. The next prime is 165641617. The reversal of 165641598 is 895146561.

165641598 is a `hidden beast` number, since 1 + 6 + 56 + 4 + 1 + 598 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 44040 + ... + 47652.

Almost surely, 2^165641598 is an apocalyptic number.

165641598 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 165641598, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (186287244).

165641598 is an abundant number, since it is smaller than the sum of its proper divisors (206932890).

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

165641598 is a wasteful number, since it uses less digits than its factorization.

165641598 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3910 (or 3901 counting only the distinct ones).

The product of its digits is 259200, while the sum is 45.

The square root of 165641598 is about 12870.1825161883. The cubic root of 165641598 is about 549.1906531242.

The spelling of 165641598 in words is "one hundred sixty-five million, six hundred forty-one thousand, five hundred ninety-eight".