138534906 has 32 divisors (see below), whose sum is σ = 285626880. Its totient is φ = 44768304.

The previous prime is 138534901. The next prime is 138534937. The reversal of 138534906 is 609435831.

It is not an unprimeable number, because it can be changed into a prime (138534901) 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, 33931 + ... + 37793.

It is an arithmetic number, because the mean of its divisors is an integer number (8925840).

Almost surely, 2^138534906 is an apocalyptic number.

138534906 is an abundant number, since it is smaller than the sum of its proper divisors (147091974).

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

138534906 is a wasteful number, since it uses less digits than its factorization.

138534906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4050.

The product of its (nonzero) digits is 77760, while the sum is 39.

The square root of 138534906 is about 11770.0852163440. The cubic root of 138534906 is about 517.4317471656.

The spelling of 138534906 in words is "one hundred thirty-eight million, five hundred thirty-four thousand, nine hundred six".