138606257 has 8 divisors (see below), whose sum is σ = 144840960. Its totient is φ = 132388960.

The previous prime is 138606229. The next prime is 138606263. The reversal of 138606257 is 752606831.

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 138606257 - 2⁸ = 138606001 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 138606257.

It is not an unprimeable number, because it can be changed into a prime (138606227) 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, 13544 + ... + 21462.

It is an arithmetic number, because the mean of its divisors is an integer number (18105120).

Almost surely, 2^138606257 is an apocalyptic number.

It is an amenable number.

138606257 is a deficient number, since it is larger than the sum of its proper divisors (6234703).

138606257 is an equidigital number, since it uses as much as digits as its factorization.

138606257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8703.

The product of its (nonzero) digits is 60480, while the sum is 38.

The square root of 138606257 is about 11773.1158577498. The cubic root of 138606257 is about 517.5205645791.

The spelling of 138606257 in words is "one hundred thirty-eight million, six hundred six thousand, two hundred fifty-seven".