16605640 has 16 divisors (see below), whose sum is σ = 37362780. Its totient is φ = 6642240.

The previous prime is 16605629. The next prime is 16605653. The reversal of 16605640 is 4650661.

It can be written as a sum of positive squares in 2 ways, for example, as 13557124 + 3048516 = 3682^2 + 1746^2 .

It is a junction number, because it is equal to n+sod(n) for n = 16605599 and 16605608.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 207531 + ... + 207610.

Almost surely, 2^16605640 is an apocalyptic number.

16605640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

16605640 is an abundant number, since it is smaller than the sum of its proper divisors (20757140).

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

16605640 is a wasteful number, since it uses less digits than its factorization.

16605640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 415152 (or 415148 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 16605640 is about 4075.0018404904. The cubic root of 16605640 is about 255.1243274291.

The spelling of 16605640 in words is "sixteen million, six hundred five thousand, six hundred forty".