138408925 has 6 divisors (see below), whose sum is σ = 171627098. Its totient is φ = 110727120.

The previous prime is 138408877. The next prime is 138408929. The reversal of 138408925 is 529804831.

It can be written as a sum of positive squares in 3 ways, for example, as 534361 + 137874564 = 731^2 + 11742^2 .

It is a de Polignac number, because none of the positive numbers 2^k-138408925 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138408929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2768154 + ... + 2768203.

Almost surely, 2^138408925 is an apocalyptic number.

It is an amenable number.

138408925 is a deficient number, since it is larger than the sum of its proper divisors (33218173).

138408925 is an equidigital number, since it uses as much as digits as its factorization.

138408925 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5536367 (or 5536362 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 40.

The square root of 138408925 is about 11764.7322536469. The cubic root of 138408925 is about 517.2748520777.

The spelling of 138408925 in words is "one hundred thirty-eight million, four hundred eight thousand, nine hundred twenty-five".