138717765 has 56 divisors (see below), whose sum is σ = 262844640. Its totient is φ = 70053984.

The previous prime is 138717749. The next prime is 138717779. The reversal of 138717765 is 567717831.

It is not a de Polignac number, because 138717765 - 2⁴ = 138717749 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 138717765.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 68254 + ... + 70256.

Almost surely, 2^138717765 is an apocalyptic number.

138717765 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

138717765 is a deficient number, since it is larger than the sum of its proper divisors (124126875).

138717765 is an equidigital number, since it uses as much as digits as its factorization.

138717765 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2045 (or 2030 counting only the distinct ones).

The product of its digits is 246960, while the sum is 45.

The square root of 138717765 is about 11777.8506103618. The cubic root of 138717765 is about 517.6593082311.

The spelling of 138717765 in words is "one hundred thirty-eight million, seven hundred seventeen thousand, seven hundred sixty-five".