138951105815 has 4 divisors (see below), whose sum is σ = 166741326984. Its totient is φ = 111160884648.

The previous prime is 138951105809. The next prime is 138951105827. The reversal of 138951105815 is 518501159831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 518501159831 = 29 ⋅17879350339.

It is a cyclic number.

It is not a de Polignac number, because 138951105815 - 2⁶ = 138951105751 is a prime.

It is a super-2 number, since 2×138951105815² (a number of 23 digits) contains 22 as substring.

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 138951105815.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13895110577 + ... + 13895110586.

It is an arithmetic number, because the mean of its divisors is an integer number (41685331746).

Almost surely, 2^138951105815 is an apocalyptic number.

138951105815 is a deficient number, since it is larger than the sum of its proper divisors (27790221169).

138951105815 is an equidigital number, since it uses as much as digits as its factorization.

138951105815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27790221168.

The product of its (nonzero) digits is 216000, while the sum is 47.

The spelling of 138951105815 in words is "one hundred thirty-eight billion, nine hundred fifty-one million, one hundred five thousand, eight hundred fifteen".