165989860 has 12 divisors (see below), whose sum is σ = 348578748. Its totient is φ = 66395936.

The previous prime is 165989839. The next prime is 165989861. The reversal of 165989860 is 68989561.

It can be written as a sum of positive squares in 2 ways, for example, as 89567296 + 76422564 = 9464^2 + 8742^2 .

It is a junction number, because it is equal to n+sod(n) for n = 165989798 and 165989807.

It is not an unprimeable number, because it can be changed into a prime (165989861) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4149727 + ... + 4149766.

It is an arithmetic number, because the mean of its divisors is an integer number (29048229).

Almost surely, 2^165989860 is an apocalyptic number.

165989860 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

165989860 is an abundant number, since it is smaller than the sum of its proper divisors (182588888).

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

165989860 is a wasteful number, since it uses less digits than its factorization.

165989860 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8299502 (or 8299500 counting only the distinct ones).

The product of its (nonzero) digits is 933120, while the sum is 52.

The square root of 165989860 is about 12883.7052123991. The cubic root of 165989860 is about 549.5752754066.

It can be divided in two parts, 1659 and 89860, that added together give a palindrome (91519).

The spelling of 165989860 in words is "one hundred sixty-five million, nine hundred eighty-nine thousand, eight hundred sixty".