138367961999 has 4 divisors (see below), whose sum is σ = 138525737064. Its totient is φ = 138210186936.

The previous prime is 138367961987. The next prime is 138367962041. The reversal of 138367961999 is 999169763831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 999169763831 = 28879 ⋅34598489.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-138367961999 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 (138367961959) 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, 78886217 + ... + 78887970.

It is an arithmetic number, because the mean of its divisors is an integer number (34631434266).

Almost surely, 2^138367961999 is an apocalyptic number.

138367961999 is a deficient number, since it is larger than the sum of its proper divisors (157775065).

138367961999 is an equidigital number, since it uses as much as digits as its factorization.

138367961999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 157775064.

The product of its digits is 119042784, while the sum is 71.

The spelling of 138367961999 in words is "one hundred thirty-eight billion, three hundred sixty-seven million, nine hundred sixty-one thousand, nine hundred ninety-nine".