138125521831 has 8 divisors (see below), whose sum is σ = 150687306000. Its totient is φ = 125564557440.

The previous prime is 138125521829. The next prime is 138125521903.

It is a happy number.

138125521831 is nontrivially palindromic in base 10.

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

It is a cyclic number.

It is not a de Polignac number, because 138125521831 - 2¹ = 138125521829 is a prime.

It is a super-2 number, since 2×138125521831² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138125521231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 178575 + ... + 555103.

It is an arithmetic number, because the mean of its divisors is an integer number (18835913250).

Almost surely, 2^138125521831 is an apocalyptic number.

138125521831 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

138125521831 is a deficient number, since it is larger than the sum of its proper divisors (12561784169).

138125521831 is a wasteful number, since it uses less digits than its factorization.

138125521831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 409889.

The product of its digits is 57600, while the sum is 40.

It can be divided in two parts, 138125 and 521831, that added together give a palindrome (659956).

The spelling of 138125521831 in words is "one hundred thirty-eight billion, one hundred twenty-five million, five hundred twenty-one thousand, eight hundred thirty-one".