165636440 has 32 divisors (see below), whose sum is σ = 394606080. Its totient is φ = 62356992.

The previous prime is 165636439. The next prime is 165636467. The reversal of 165636440 is 44636561.

It is a self number, because there is not a number n which added to its sum of digits gives 165636440.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 121112 + ... + 122471.

It is an arithmetic number, because the mean of its divisors is an integer number (12331440).

Almost surely, 2^165636440 is an apocalyptic number.

165636440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

165636440 is an abundant number, since it is smaller than the sum of its proper divisors (228969640).

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

165636440 is a wasteful number, since it uses less digits than its factorization.

165636440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 243611 (or 243607 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 35.

The square root of 165636440 is about 12869.9821289697. The cubic root of 165636440 is about 549.1849525538.

The spelling of 165636440 in words is "one hundred sixty-five million, six hundred thirty-six thousand, four hundred forty".