138634530 has 64 divisors (see below), whose sum is σ = 342921600. Its totient is φ = 35847680.

The previous prime is 138634487. The next prime is 138634553. The reversal of 138634530 is 35436831.

138634530 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 138634491 and 138634500.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 330661 + ... + 331079.

It is an arithmetic number, because the mean of its divisors is an integer number (5358150).

Almost surely, 2^138634530 is an apocalyptic number.

138634530 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 138634530, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (171460800).

138634530 is an abundant number, since it is smaller than the sum of its proper divisors (204287070).

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

138634530 is a wasteful number, since it uses less digits than its factorization.

138634530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 739.

The product of its (nonzero) digits is 25920, while the sum is 33.

The square root of 138634530 is about 11774.3165406745. The cubic root of 138634530 is about 517.5557502542. Note that the first 3 decimals are identical.

The spelling of 138634530 in words is "one hundred thirty-eight million, six hundred thirty-four thousand, five hundred thirty".