155550 has 48 divisors (see below), whose sum is σ = 415152. Its totient is φ = 38400.

The previous prime is 155539. The next prime is 155557. The reversal of 155550 is 55551.

155550 is nontrivially palindromic in base 13.

It is a congruent number.

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

155550 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 23 ways as a sum of consecutive naturals, for example, 2520 + ... + 2580.

It is an arithmetic number, because the mean of its divisors is an integer number (8649).

2¹⁵⁵⁵⁵⁰ is an apocalyptic number.

155550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 155550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (207576).

155550 is an abundant number, since it is smaller than the sum of its proper divisors (259602).

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

155550 is a wasteful number, since it uses less digits than its factorization.

155550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93 (or 88 counting only the distinct ones).

The product of its (nonzero) digits is 625, while the sum is 21.

The square root of 155550 is about 394.3982758583. The cubic root of 155550 is about 53.7803146104.

Subtracting from 155550 its reverse (55551), we obtain a palindrome (99999).

It can be divided in two parts, 15 and 5550, that added together give a triangular number (5565 = T₁₀₅).

The spelling of 155550 in words is "one hundred fifty-five thousand, five hundred fifty".