138515845121 has 4 divisors (see below), whose sum is σ = 138700287744. Its totient is φ = 138331402500.

The previous prime is 138515845087. The next prime is 138515845129. The reversal of 138515845121 is 121548515831.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 138515845121 - 2¹⁰ = 138515844097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138515845129) 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, 92220185 + ... + 92221686.

It is an arithmetic number, because the mean of its divisors is an integer number (34675071936).

Almost surely, 2^138515845121 is an apocalyptic number.

It is an amenable number.

138515845121 is a deficient number, since it is larger than the sum of its proper divisors (184442623).

138515845121 is an equidigital number, since it uses as much as digits as its factorization.

138515845121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 184442622.

The product of its digits is 192000, while the sum is 44.

The spelling of 138515845121 in words is "one hundred thirty-eight billion, five hundred fifteen million, eight hundred forty-five thousand, one hundred twenty-one".