138621008 has 20 divisors (see below), whose sum is σ = 270696960. Its totient is φ = 68763744.

The previous prime is 138620987. The next prime is 138621013. The reversal of 138621008 is 800126831.

138621008 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32078 + ... + 36141.

It is an arithmetic number, because the mean of its divisors is an integer number (13534848).

Almost surely, 2^138621008 is an apocalyptic number.

It is an amenable number.

138621008 is a deficient number, since it is larger than the sum of its proper divisors (132075952).

138621008 is a wasteful number, since it uses less digits than its factorization.

138621008 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68354 (or 68348 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 29.

The square root of 138621008 is about 11773.7423107523. The cubic root of 138621008 is about 517.5389227572.

Adding to 138621008 its reverse (800126831), we get a palindrome (938747839).

The spelling of 138621008 in words is "one hundred thirty-eight million, six hundred twenty-one thousand, eight".