138260240 has 20 divisors (see below), whose sum is σ = 321455244. Its totient is φ = 55304064.

The previous prime is 138260233. The next prime is 138260251. The reversal of 138260240 is 42062831.

138260240 = 279² + 280² + ... + 758².

It can be written as a sum of positive squares in 2 ways, for example, as 14961424 + 123298816 = 3868^2 + 11104^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 864047 + ... + 864206.

Almost surely, 2^138260240 is an apocalyptic number.

138260240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138260240 is an abundant number, since it is smaller than the sum of its proper divisors (183195004).

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

138260240 is a wasteful number, since it uses less digits than its factorization.

138260240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1728266 (or 1728260 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 26.

The square root of 138260240 is about 11758.4114573356. The cubic root of 138260240 is about 517.0895591899.

The spelling of 138260240 in words is "one hundred thirty-eight million, two hundred sixty thousand, two hundred forty".