138908456 has 8 divisors (see below), whose sum is σ = 260453370. Its totient is φ = 69454224.

The previous prime is 138908417. The next prime is 138908467. The reversal of 138908456 is 654809831.

It can be written as a sum of positive squares in only one way, i.e., 123432100 + 15476356 = 11110^2 + 3934^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8681771 + ... + 8681786.

Almost surely, 2^138908456 is an apocalyptic number.

It is an amenable number.

138908456 is a deficient number, since it is larger than the sum of its proper divisors (121544914).

138908456 is a wasteful number, since it uses less digits than its factorization.

138908456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17363563 (or 17363559 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 44.

The square root of 138908456 is about 11785.9431527562. The cubic root of 138908456 is about 517.8964030091.

The spelling of 138908456 in words is "one hundred thirty-eight million, nine hundred eight thousand, four hundred fifty-six".