165990720 has 224 divisors, whose sum is σ = 638178048. Its totient is φ = 35684352.

The previous prime is 165990679. The next prime is 165990733. The reversal of 165990720 is 27099561.

It is a tau number, because it is divible by the number of its divisors (224).

It is a super-2 number, since 2×165990720² = 55105838252236800, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 113514 + ... + 114966.

Almost surely, 2^165990720 is an apocalyptic number.

165990720 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 165990720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (319089024).

165990720 is an abundant number, since it is smaller than the sum of its proper divisors (472187328).

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

165990720 is a wasteful number, since it uses less digits than its factorization.

165990720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1497 (or 1487 counting only the distinct ones).

The product of its (nonzero) digits is 34020, while the sum is 39.

The square root of 165990720 is about 12883.7385878479. The cubic root of 165990720 is about 549.5762245287.

The spelling of 165990720 in words is "one hundred sixty-five million, nine hundred ninety thousand, seven hundred twenty".