138908849 has 4 divisors (see below), whose sum is σ = 138968064. Its totient is φ = 138849636.

The previous prime is 138908843. The next prime is 138908851. The reversal of 138908849 is 948809831.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 138908849 - 2⁸ = 138908593 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 138908797 and 138908806.

It is not an unprimeable number, because it can be changed into a prime (138908843) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25937 + ... + 30830.

It is an arithmetic number, because the mean of its divisors is an integer number (34742016).

Almost surely, 2^138908849 is an apocalyptic number.

It is an amenable number.

138908849 is a deficient number, since it is larger than the sum of its proper divisors (59215).

138908849 is an equidigital number, since it uses as much as digits as its factorization.

138908849 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59214.

The product of its (nonzero) digits is 497664, while the sum is 50.

The square root of 138908849 is about 11785.9598251479. The cubic root of 138908849 is about 517.8968914197.

The spelling of 138908849 in words is "one hundred thirty-eight million, nine hundred eight thousand, eight hundred forty-nine".