123531500 has 48 divisors (see below), whose sum is σ = 272432160. Its totient is φ = 48929600.

The previous prime is 123531479. The next prime is 123531509. The reversal of 123531500 is 5135321.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is not an unprimeable number, because it can be changed into a prime (123531509) 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, 52346 + ... + 54654.

It is an arithmetic number, because the mean of its divisors is an integer number (5675670).

Almost surely, 2^123531500 is an apocalyptic number.

123531500 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 123531500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (136216080).

123531500 is an abundant number, since it is smaller than the sum of its proper divisors (148900660).

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

123531500 is a wasteful number, since it uses less digits than its factorization.

123531500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2435 (or 2423 counting only the distinct ones).

The product of its (nonzero) digits is 450, while the sum is 20.

The square root of 123531500 is about 11114.4725470892. The cubic root of 123531500 is about 498.0342820333.

Adding to 123531500 its reverse (5135321), we get a palindrome (128666821).

The spelling of 123531500 in words is "one hundred twenty-three million, five hundred thirty-one thousand, five hundred".