138169665 has 32 divisors (see below), whose sum is σ = 246954240. Its totient is φ = 73294848.

The previous prime is 138169649. The next prime is 138169687. The reversal of 138169665 is 566961831.

It is not a de Polignac number, because 138169665 - 2⁴ = 138169649 is a prime.

It is a super-3 number, since 3×138169665³ (a number of 25 digits) contains 333 as substring.

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 138169665.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 23404 + ... + 28706.

It is an arithmetic number, because the mean of its divisors is an integer number (7717320).

Almost surely, 2^138169665 is an apocalyptic number.

138169665 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

138169665 is a deficient number, since it is larger than the sum of its proper divisors (108784575).

138169665 is a wasteful number, since it uses less digits than its factorization.

138169665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5510 (or 5504 counting only the distinct ones).

The product of its digits is 233280, while the sum is 45.

The square root of 138169665 is about 11754.5593281926. The cubic root of 138169665 is about 516.9766185067.

The spelling of 138169665 in words is "one hundred thirty-eight million, one hundred sixty-nine thousand, six hundred sixty-five".