138995665 has 8 divisors (see below), whose sum is σ = 168514920. Its totient is φ = 110049792.

The previous prime is 138995663. The next prime is 138995669. The reversal of 138995665 is 566599831.

It can be written as a sum of positive squares in 4 ways, for example, as 43718544 + 95277121 = 6612^2 + 9761^2 .

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 138995665 - 2¹ = 138995663 is a prime.

It is not an unprimeable number, because it can be changed into a prime (138995663) 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, 142810 + ... + 143779.

It is an arithmetic number, because the mean of its divisors is an integer number (21064365).

Almost surely, 2^138995665 is an apocalyptic number.

It is an amenable number.

138995665 is a deficient number, since it is larger than the sum of its proper divisors (29519255).

138995665 is an equidigital number, since it uses as much as digits as its factorization.

138995665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 286691.

The product of its digits is 1749600, while the sum is 52.

The square root of 138995665 is about 11789.6422761677. The cubic root of 138995665 is about 518.0047616125.

The spelling of 138995665 in words is "one hundred thirty-eight million, nine hundred ninety-five thousand, six hundred sixty-five".