138531624 has 96 divisors (see below), whose sum is σ = 439538400. Its totient is φ = 35978880.

The previous prime is 138531611. The next prime is 138531647. The reversal of 138531624 is 426135831.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7582 + ... + 18290.

It is an arithmetic number, because the mean of its divisors is an integer number (4578525).

Almost surely, 2^138531624 is an apocalyptic number.

138531624 is a gapful number since it is divisible by the number (14) 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 138531624, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (219769200).

138531624 is an abundant number, since it is smaller than the sum of its proper divisors (301006776).

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

138531624 is a wasteful number, since it uses less digits than its factorization.

138531624 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10743 (or 10732 counting only the distinct ones).

The product of its digits is 17280, while the sum is 33.

The square root of 138531624 is about 11769.9457942677. The cubic root of 138531624 is about 517.4276610127.

The spelling of 138531624 in words is "one hundred thirty-eight million, five hundred thirty-one thousand, six hundred twenty-four".