123540 has 48 divisors (see below), whose sum is σ = 362880. Its totient is φ = 31360.

The previous prime is 123527. The next prime is 123547. The reversal of 123540 is 45321.

123540 = T₁₀₁ + T₁₀₂ + ... + T₁₂₀.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123547) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1705 + ... + 1775.

It is an arithmetic number, because the mean of its divisors is an integer number (7560).

2¹²³⁵⁴⁰ is an apocalyptic number.

123540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 123540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (181440).

123540 is an abundant number, since it is smaller than the sum of its proper divisors (239340).

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

123540 is a wasteful number, since it uses less digits than its factorization.

123540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112 (or 110 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 15.

The square root of 123540 is about 351.4825742480. The cubic root of 123540 is about 49.8045704745.

Adding to 123540 its reverse (45321), we get a palindrome (168861).

It can be divided in two parts, 1235 and 40, that added together give a triangular number (1275 = T₅₀).

The spelling of 123540 in words is "one hundred twenty-three thousand, five hundred forty".