138709481 has 16 divisors (see below), whose sum is σ = 153584640. Its totient is φ = 124684560.

The previous prime is 138709471. The next prime is 138709499. The reversal of 138709481 is 184907831.

It is a cyclic number.

It is not a de Polignac number, because 138709481 - 2²² = 134515177 is a prime.

It is a super-2 number, since 2×138709481² = 38480640238578722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138709471) by changing a digit.

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 in 15 ways as a sum of consecutive naturals, for example, 56036 + ... + 58458.

It is an arithmetic number, because the mean of its divisors is an integer number (9599040).

Almost surely, 2^138709481 is an apocalyptic number.

It is an amenable number.

138709481 is a deficient number, since it is larger than the sum of its proper divisors (14875159).

138709481 is a wasteful number, since it uses less digits than its factorization.

138709481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2596.

The product of its (nonzero) digits is 48384, while the sum is 41.

The square root of 138709481 is about 11777.4989280407. The cubic root of 138709481 is about 517.6490034344.

The spelling of 138709481 in words is "one hundred thirty-eight million, seven hundred nine thousand, four hundred eighty-one".