165637871520 has 192 divisors, whose sum is σ = 575589006720. Its totient is φ = 39703347200.

The previous prime is 165637871459. The next prime is 165637871521. The reversal of 165637871520 is 25178736561.

It is a super-2 number, since 2×165637871520² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (165637871521) 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, 293680 + ... + 646160.

It is an arithmetic number, because the mean of its divisors is an integer number (2997859410).

Almost surely, 2^165637871520 is an apocalyptic number.

165637871520 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 165637871520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (287794503360).

165637871520 is an abundant number, since it is smaller than the sum of its proper divisors (409951135200).

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

165637871520 is a wasteful number, since it uses less digits than its factorization.

165637871520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 352599 (or 352591 counting only the distinct ones).

The product of its (nonzero) digits is 2116800, while the sum is 51.

The spelling of 165637871520 in words is "one hundred sixty-five billion, six hundred thirty-seven million, eight hundred seventy-one thousand, five hundred twenty".