138965657 has 8 divisors (see below), whose sum is σ = 139834656. Its totient is φ = 138100032.

The previous prime is 138965641. The next prime is 138965663. The reversal of 138965657 is 756569831.

It is a happy number.

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 138965657 - 2⁴ = 138965641 is a prime.

It is a super-2 number, since 2×138965657² = 38622907650883298, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138965357) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 156938 + ... + 157820.

It is an arithmetic number, because the mean of its divisors is an integer number (17479332).

Almost surely, 2^138965657 is an apocalyptic number.

It is an amenable number.

138965657 is a deficient number, since it is larger than the sum of its proper divisors (868999).

138965657 is an equidigital number, since it uses as much as digits as its factorization.

138965657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1687.

The product of its digits is 1360800, while the sum is 50.

The square root of 138965657 is about 11788.3695649568. The cubic root of 138965657 is about 517.9674812996.

The spelling of 138965657 in words is "one hundred thirty-eight million, nine hundred sixty-five thousand, six hundred fifty-seven".