138053661517 has 4 divisors (see below), whose sum is σ = 141784841596. Its totient is φ = 134322481440.

The previous prime is 138053661511. The next prime is 138053661539. The reversal of 138053661517 is 715166350831.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 132034849956 + 6018811561 = 363366^2 + 77581^2 .

It is a cyclic number.

It is not a de Polignac number, because 138053661517 - 2²³ = 138045272909 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 (138053661511) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1865589984 + ... + 1865590057.

It is an arithmetic number, because the mean of its divisors is an integer number (35446210399).

Almost surely, 2^138053661517 is an apocalyptic number.

It is an amenable number.

138053661517 is a deficient number, since it is larger than the sum of its proper divisors (3731180079).

138053661517 is an equidigital number, since it uses as much as digits as its factorization.

138053661517 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3731180078.

The product of its (nonzero) digits is 453600, while the sum is 46.

The spelling of 138053661517 in words is "one hundred thirty-eight billion, fifty-three million, six hundred sixty-one thousand, five hundred seventeen".