138814681 has 8 divisors (see below), whose sum is σ = 140090184. Its totient is φ = 137544960.

The previous prime is 138814667. The next prime is 138814691. The reversal of 138814681 is 186418831.

It can be written as a sum of positive squares in 4 ways, for example, as 2509056 + 136305625 = 1584^2 + 11675^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 138814681 - 2¹⁵ = 138781913 is a prime.

It is a super-2 number, since 2×138814681² = 38539031322263522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138814691) 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 7 ways as a sum of consecutive naturals, for example, 57111 + ... + 59491.

It is an arithmetic number, because the mean of its divisors is an integer number (17511273).

Almost surely, 2^138814681 is an apocalyptic number.

It is an amenable number.

138814681 is a deficient number, since it is larger than the sum of its proper divisors (1275503).

138814681 is a wasteful number, since it uses less digits than its factorization.

138814681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2891.

The product of its digits is 36864, while the sum is 40.

The square root of 138814681 is about 11781.9642250348. The cubic root of 138814681 is about 517.7798354284.

The spelling of 138814681 in words is "one hundred thirty-eight million, eight hundred fourteen thousand, six hundred eighty-one".