155790 has 32 divisors (see below), whose sum is σ = 416160. Its totient is φ = 41472.

The previous prime is 155783. The next prime is 155797. The reversal of 155790 is 97551.

It is an interprime number because it is at equal distance from previous prime (155783) and next prime (155797).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155797) by changing a digit.

155790 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19 + ... + 558.

It is an arithmetic number, because the mean of its divisors is an integer number (13005).

2¹⁵⁵⁷⁹⁰ is an apocalyptic number.

155790 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 155790, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (208080).

155790 is an abundant number, since it is smaller than the sum of its proper divisors (260370).

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

155790 is a wasteful number, since it uses less digits than its factorization.

155790 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 593 (or 587 counting only the distinct ones).

The product of its (nonzero) digits is 1575, while the sum is 27.

The square root of 155790 is about 394.7024195517. The cubic root of 155790 is about 53.8079598326.

The spelling of 155790 in words is "one hundred fifty-five thousand, seven hundred ninety".