138142331 has 4 divisors (see below), whose sum is σ = 145413000. Its totient is φ = 130871664.

The previous prime is 138142307. The next prime is 138142339. The reversal of 138142331 is 133241831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 133241831 = 223 ⋅597497.

It is a cyclic number.

It is not a de Polignac number, because 138142331 - 2¹⁴ = 138125947 is a prime.

It is a super-3 number, since 3×138142331³ (a number of 25 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

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 138142331.

It is not an unprimeable number, because it can be changed into a prime (138142339) 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, 3635306 + ... + 3635343.

It is an arithmetic number, because the mean of its divisors is an integer number (36353250).

Almost surely, 2^138142331 is an apocalyptic number.

138142331 is a deficient number, since it is larger than the sum of its proper divisors (7270669).

138142331 is an equidigital number, since it uses as much as digits as its factorization.

138142331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7270668.

The product of its digits is 1728, while the sum is 26.

The square root of 138142331 is about 11753.3965729061. The cubic root of 138142331 is about 516.9425252276.

The spelling of 138142331 in words is "one hundred thirty-eight million, one hundred forty-two thousand, three hundred thirty-one".