138195020849 has 4 divisors (see below), whose sum is σ = 138506973936. Its totient is φ = 137883067764.

The previous prime is 138195020809. The next prime is 138195020867. The reversal of 138195020849 is 948020591831.

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 138195020849 - 2¹² = 138195016753 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 138195020797 and 138195020806.

It is not an unprimeable number, because it can be changed into a prime (138195020809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 155975879 + ... + 155976764.

It is an arithmetic number, because the mean of its divisors is an integer number (34626743484).

Almost surely, 2^138195020849 is an apocalyptic number.

It is an amenable number.

138195020849 is a deficient number, since it is larger than the sum of its proper divisors (311953087).

138195020849 is an equidigital number, since it uses as much as digits as its factorization.

138195020849 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 311953086.

The product of its (nonzero) digits is 622080, while the sum is 50.

The spelling of 138195020849 in words is "one hundred thirty-eight billion, one hundred ninety-five million, twenty thousand, eight hundred forty-nine".