138242831 has 2 divisors, whose sum is σ = 138242832. Its totient is φ = 138242830.

The previous prime is 138242821. The next prime is 138242833.

138242831 is nontrivially palindromic in base 10.

It is a strong prime.

It is a palprime.

It is a cyclic number.

It is not a de Polignac number, because 138242831 - 2¹⁴ = 138226447 is a prime.

It is a super-2 number, since 2×138242831² = 38222160645789122, which contains 22 as substring.

Together with 138242833, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138242833) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69121415 + 69121416.

It is an arithmetic number, because the mean of its divisors is an integer number (69121416).

Almost surely, 2^138242831 is an apocalyptic number.

138242831 is a deficient number, since it is larger than the sum of its proper divisors (1).

138242831 is an equidigital number, since it uses as much as digits as its factorization.

138242831 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9216, while the sum is 32.

The square root of 138242831 is about 11757.6711554627. The cubic root of 138242831 is about 517.0678552159.

The spelling of 138242831 in words is "one hundred thirty-eight million, two hundred forty-two thousand, eight hundred thirty-one".