165906556 has 24 divisors (see below), whose sum is σ = 312730880. Its totient is φ = 76758192.

The previous prime is 165906551. The next prime is 165906571. The reversal of 165906556 is 655609561.

165906556 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×165906556² = 55049970647562272, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (43).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165906551) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22116 + ... + 28651.

Almost surely, 2^165906556 is an apocalyptic number.

It is an amenable number.

165906556 is a deficient number, since it is larger than the sum of its proper divisors (146824324).

165906556 is a wasteful number, since it uses less digits than its factorization.

165906556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50833 (or 50831 counting only the distinct ones).

The product of its (nonzero) digits is 243000, while the sum is 43.

The square root of 165906556 is about 12880.4718857657. The cubic root of 165906556 is about 549.4833230436.

The spelling of 165906556 in words is "one hundred sixty-five million, nine hundred six thousand, five hundred fifty-six".