165689984 has 16 divisors (see below), whose sum is σ = 330085770. Its totient is φ = 82844928.

The previous prime is 165689977. The next prime is 165690011. The reversal of 165689984 is 489986561.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 165688384 + 1600 = 12872^2 + 40^2 .

It is a tau number, because it is divible by the number of its divisors (16).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 647099 + ... + 647354.

Almost surely, 2^165689984 is an apocalyptic number.

It is an amenable number.

165689984 is a deficient number, since it is larger than the sum of its proper divisors (164395786).

165689984 is an equidigital number, since it uses as much as digits as its factorization.

165689984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1294467 (or 1294455 counting only the distinct ones).

The product of its digits is 3732480, while the sum is 56.

The square root of 165689984 is about 12872.0621502539. The cubic root of 165689984 is about 549.2441230904.

The spelling of 165689984 in words is "one hundred sixty-five million, six hundred eighty-nine thousand, nine hundred eighty-four".