155556 has 36 divisors (see below), whose sum is σ = 409500. Its totient is φ = 49728.

The previous prime is 155539. The next prime is 155557. The reversal of 155556 is 655551.

It can be written as a sum of positive squares in 2 ways, for example, as 46656 + 108900 = 216^2 + 330^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is an Ulam number.

It is a plaindrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (155557) by changing a digit.

155556 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 970 + ... + 1118.

It is an arithmetic number, because the mean of its divisors is an integer number (11375).

2¹⁵⁵⁵⁵⁶ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 155556, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (204750).

155556 is an abundant number, since it is smaller than the sum of its proper divisors (253944).

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

155556 is a wasteful number, since it uses less digits than its factorization.

155556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 188 (or 183 counting only the distinct ones).

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

The square root of 155556 is about 394.4058823091. The cubic root of 155556 is about 53.7810060874.

The spelling of 155556 in words is "one hundred fifty-five thousand, five hundred fifty-six".