138277885 has 4 divisors (see below), whose sum is σ = 165933468. Its totient is φ = 110622304.

The previous prime is 138277873. The next prime is 138277897. The reversal of 138277885 is 588772831.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 588772831 = 97 ⋅6069823.

It is an interprime number because it is at equal distance from previous prime (138277873) and next prime (138277897).

It can be written as a sum of positive squares in 2 ways, for example, as 75377124 + 62900761 = 8682^2 + 7931^2 .

It is a cyclic number.

It is not a de Polignac number, because 138277885 - 2¹³ = 138269693 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13827784 + ... + 13827793.

It is an arithmetic number, because the mean of its divisors is an integer number (41483367).

Almost surely, 2^138277885 is an apocalyptic number.

It is an amenable number.

138277885 is a deficient number, since it is larger than the sum of its proper divisors (27655583).

138277885 is an equidigital number, since it uses as much as digits as its factorization.

138277885 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27655582.

The product of its digits is 752640, while the sum is 49.

The square root of 138277885 is about 11759.1617473356. The cubic root of 138277885 is about 517.1115555285. Note that the first 3 decimals are identical.

It can be divided in two parts, 13827 and 7885, that added together give a palindrome (21712).

The spelling of 138277885 in words is "one hundred thirty-eight million, two hundred seventy-seven thousand, eight hundred eighty-five".