138287885 has 8 divisors (see below), whose sum is σ = 166392600. Its totient is φ = 110332224.

The previous prime is 138287881. The next prime is 138287899. The reversal of 138287885 is 588782831.

It can be written as a sum of positive squares in 4 ways, for example, as 20912329 + 117375556 = 4573^2 + 10834^2 .

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 138287885 - 2² = 138287881 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138287881) 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 7 ways as a sum of consecutive naturals, for example, 35210 + ... + 38939.

It is an arithmetic number, because the mean of its divisors is an integer number (20799075).

Almost surely, 2^138287885 is an apocalyptic number.

It is an amenable number.

138287885 is a deficient number, since it is larger than the sum of its proper divisors (28104715).

138287885 is an equidigital number, since it uses as much as digits as its factorization.

138287885 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74527.

The product of its digits is 860160, while the sum is 50.

The square root of 138287885 is about 11759.5869400247. The cubic root of 138287885 is about 517.1240207440.

The spelling of 138287885 in words is "one hundred thirty-eight million, two hundred eighty-seven thousand, eight hundred eighty-five".