138440782 has 4 divisors (see below), whose sum is σ = 207661176. Its totient is φ = 69220390.

The previous prime is 138440767. The next prime is 138440789. The reversal of 138440782 is 287044831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 287044831 = 1579 ⋅181789.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138440789) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34610194 + ... + 34610197.

It is an arithmetic number, because the mean of its divisors is an integer number (51915294).

Almost surely, 2^138440782 is an apocalyptic number.

138440782 is a deficient number, since it is larger than the sum of its proper divisors (69220394).

138440782 is an equidigital number, since it uses as much as digits as its factorization.

138440782 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69220393.

The product of its (nonzero) digits is 43008, while the sum is 37.

The square root of 138440782 is about 11766.0860952145. The cubic root of 138440782 is about 517.3145353588.

The spelling of 138440782 in words is "one hundred thirty-eight million, four hundred forty thousand, seven hundred eighty-two".