138981077 has 4 divisors (see below), whose sum is σ = 139425420. Its totient is φ = 138536736.

The previous prime is 138981047. The next prime is 138981097. The reversal of 138981077 is 770189831.

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

It can be written as a sum of positive squares in 2 ways, for example, as 34000561 + 104980516 = 5831^2 + 10246^2 .

It is a cyclic number.

It is not a de Polignac number, because 138981077 - 2⁶ = 138981013 is a prime.

It is a super-3 number, since 3×138981077³ (a number of 25 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138981047) 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, 221702 + ... + 222327.

It is an arithmetic number, because the mean of its divisors is an integer number (34856355).

Almost surely, 2^138981077 is an apocalyptic number.

It is an amenable number.

138981077 is a deficient number, since it is larger than the sum of its proper divisors (444343).

138981077 is an equidigital number, since it uses as much as digits as its factorization.

138981077 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 444342.

The product of its (nonzero) digits is 84672, while the sum is 44.

The square root of 138981077 is about 11789.0235812810. The cubic root of 138981077 is about 517.9866389422.

The spelling of 138981077 in words is "one hundred thirty-eight million, nine hundred eighty-one thousand, seventy-seven".