138857765 has 8 divisors (see below), whose sum is σ = 166696728. Its totient is φ = 111041280.

The previous prime is 138857759. The next prime is 138857783. The reversal of 138857765 is 567758831.

It can be written as a sum of positive squares in 4 ways, for example, as 889249 + 137968516 = 943^2 + 11746^2 .

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

It is not a de Polignac number, because 138857765 - 2⁴ = 138857749 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14585 + ... + 22145.

It is an arithmetic number, because the mean of its divisors is an integer number (20837091).

Almost surely, 2^138857765 is an apocalyptic number.

It is an amenable number.

138857765 is a deficient number, since it is larger than the sum of its proper divisors (27838963).

138857765 is an equidigital number, since it uses as much as digits as its factorization.

138857765 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11239.

The product of its digits is 1411200, while the sum is 50.

The square root of 138857765 is about 11783.7924710171. The cubic root of 138857765 is about 517.8333977720.

The spelling of 138857765 in words is "one hundred thirty-eight million, eight hundred fifty-seven thousand, seven hundred sixty-five".