138781390 has 16 divisors (see below), whose sum is σ = 272516400. Its totient is φ = 50465920.

The previous prime is 138781367. The next prime is 138781399. The reversal of 138781390 is 93187831.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138781399) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 630715 + ... + 630934.

It is an arithmetic number, because the mean of its divisors is an integer number (17032275).

Almost surely, 2^138781390 is an apocalyptic number.

138781390 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

138781390 is a deficient number, since it is larger than the sum of its proper divisors (133735010).

138781390 is a wasteful number, since it uses less digits than its factorization.

138781390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1261667.

The product of its (nonzero) digits is 36288, while the sum is 40.

The square root of 138781390 is about 11780.5513453318. The cubic root of 138781390 is about 517.7384402231.

The spelling of 138781390 in words is "one hundred thirty-eight million, seven hundred eighty-one thousand, three hundred ninety".