165501640 has 16 divisors (see below), whose sum is σ = 372378780. Its totient is φ = 66200640.

The previous prime is 165501631. The next prime is 165501671. The reversal of 165501640 is 46105561.

It can be written as a sum of positive squares in 2 ways, for example, as 154703844 + 10797796 = 12438^2 + 3286^2 .

It is a junction number, because it is equal to n+sod(n) for n = 165501599 and 165501608.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2068731 + ... + 2068810.

Almost surely, 2^165501640 is an apocalyptic number.

165501640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

165501640 is an abundant number, since it is smaller than the sum of its proper divisors (206877140).

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

165501640 is a wasteful number, since it uses less digits than its factorization.

165501640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4137552 (or 4137548 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 28.

The square root of 165501640 is about 12864.7440705208. The cubic root of 165501640 is about 549.0359309509.

The spelling of 165501640 in words is "one hundred sixty-five million, five hundred one thousand, six hundred forty".