165249840 has 320 divisors, whose sum is σ = 639959040. Its totient is φ = 34421760.

The previous prime is 165249839. The next prime is 165249841. The reversal of 165249840 is 48942561.

It is an interprime number because it is at equal distance from previous prime (165249839) and next prime (165249841).

It is not an unprimeable number, because it can be changed into a prime (165249841) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 989437 + ... + 989603.

It is an arithmetic number, because the mean of its divisors is an integer number (1999872).

Almost surely, 2^165249840 is an apocalyptic number.

165249840 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 165249840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (319979520).

165249840 is an abundant number, since it is smaller than the sum of its proper divisors (474709200).

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

165249840 is a wasteful number, since it uses less digits than its factorization.

165249840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 240 (or 234 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 39.

The square root of 165249840 is about 12854.9539089022. The cubic root of 165249840 is about 548.7573487807.

The spelling of 165249840 in words is "one hundred sixty-five million, two hundred forty-nine thousand, eight hundred forty".