155565 has 12 divisors (see below), whose sum is σ = 269724. Its totient is φ = 82944.

The previous prime is 155557. The next prime is 155569. The reversal of 155565 is 565551.

It can be written as a sum of positive squares in 2 ways, for example, as 21609 + 133956 = 147^2 + 366^2 .

It is not a de Polignac number, because 155565 - 2³ = 155557 is a prime.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155569) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1684 + ... + 1773.

It is an arithmetic number, because the mean of its divisors is an integer number (22477).

2¹⁵⁵⁵⁶⁵ is an apocalyptic number.

155565 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

155565 is a deficient number, since it is larger than the sum of its proper divisors (114159).

155565 is a wasteful number, since it uses less digits than its factorization.

155565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3468 (or 3465 counting only the distinct ones).

The product of its digits is 3750, while the sum is 27.

The square root of 155565 is about 394.4172917102. The cubic root of 155565 is about 53.7820432695.

The spelling of 155565 in words is "one hundred fifty-five thousand, five hundred sixty-five".