138431212537 has 8 divisors (see below), whose sum is σ = 138963693960. Its totient is φ = 137898864000.

The previous prime is 138431212531. The next prime is 138431212553. The reversal of 138431212537 is 735212134831.

It is a happy number.

138431212537 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 8554585081 + 129876627456 = 92491^2 + 360384^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-138431212537 is a prime.

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 138431212537.

It is not an unprimeable number, because it can be changed into a prime (138431212531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2392683 + ... + 2449855.

It is an arithmetic number, because the mean of its divisors is an integer number (17370461745).

Almost surely, 2^138431212537 is an apocalyptic number.

It is an amenable number.

138431212537 is a deficient number, since it is larger than the sum of its proper divisors (532481423).

138431212537 is an equidigital number, since it uses as much as digits as its factorization.

138431212537 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66443.

The product of its digits is 120960, while the sum is 40.

The spelling of 138431212537 in words is "one hundred thirty-eight billion, four hundred thirty-one million, two hundred twelve thousand, five hundred thirty-seven".