138442236 has 24 divisors (see below), whose sum is σ = 325175424. Its totient is φ = 45841200.

The previous prime is 138442231. The next prime is 138442253. The reversal of 138442236 is 632244831.

It is a junction number, because it is equal to n+sod(n) for n = 138442197 and 138442206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138442231) 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 7 ways as a sum of consecutive naturals, for example, 36390 + ... + 40013.

It is an arithmetic number, because the mean of its divisors is an integer number (13548976).

Almost surely, 2^138442236 is an apocalyptic number.

It is an amenable number.

138442236 is an abundant number, since it is smaller than the sum of its proper divisors (186733188).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

138442236 is a wasteful number, since it uses less digits than its factorization.

138442236 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76561 (or 76559 counting only the distinct ones).

The product of its digits is 27648, while the sum is 33.

The square root of 138442236 is about 11766.1478828034. The cubic root of 138442236 is about 517.3163464165.

The spelling of 138442236 in words is "one hundred thirty-eight million, four hundred forty-two thousand, two hundred thirty-six".