138684557 has 8 divisors (see below), whose sum is σ = 151656672. Its totient is φ = 125773200.

The previous prime is 138684551. The next prime is 138684563. The reversal of 138684557 is 755486831.

It is an interprime number because it is at equal distance from previous prime (138684551) and next prime (138684563).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-138684557 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 (138684551) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10343 + ... + 19604.

It is an arithmetic number, because the mean of its divisors is an integer number (18957084).

Almost surely, 2^138684557 is an apocalyptic number.

It is an amenable number.

138684557 is a deficient number, since it is larger than the sum of its proper divisors (12972115).

138684557 is a wasteful number, since it uses less digits than its factorization.

138684557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30379.

The product of its digits is 806400, while the sum is 47.

The square root of 138684557 is about 11776.4407611128. The cubic root of 138684557 is about 517.6179970065.

The spelling of 138684557 in words is "one hundred thirty-eight million, six hundred eighty-four thousand, five hundred fifty-seven".