138647739 has 4 divisors (see below), whose sum is σ = 184863656. Its totient is φ = 92431824.

The previous prime is 138647713. The next prime is 138647759. The reversal of 138647739 is 937746831.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 138647739 - 2¹¹ = 138645691 is a prime.

It is a super-3 number, since 3×138647739³ (a number of 25 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138647759) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23107954 + ... + 23107959.

It is an arithmetic number, because the mean of its divisors is an integer number (46215914).

Almost surely, 2^138647739 is an apocalyptic number.

138647739 is a deficient number, since it is larger than the sum of its proper divisors (46215917).

138647739 is an equidigital number, since it uses as much as digits as its factorization.

138647739 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46215916.

The product of its digits is 762048, while the sum is 48.

The square root of 138647739 is about 11774.8774515916. The cubic root of 138647739 is about 517.5721871808.

The spelling of 138647739 in words is "one hundred thirty-eight million, six hundred forty-seven thousand, seven hundred thirty-nine".