138227920 has 40 divisors (see below), whose sum is σ = 332467560. Its totient is φ = 53383680.

The previous prime is 138227899. The next prime is 138227923. The reversal of 138227920 is 29722831.

It can be written as a sum of positive squares in 4 ways, for example, as 26460736 + 111767184 = 5144^2 + 10572^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138227923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27471 + ... + 32110.

It is an arithmetic number, because the mean of its divisors is an integer number (8311689).

Almost surely, 2^138227920 is an apocalyptic number.

138227920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138227920 is an abundant number, since it is smaller than the sum of its proper divisors (194239640).

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

138227920 is a wasteful number, since it uses less digits than its factorization.

138227920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59623 (or 59617 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 34.

The square root of 138227920 is about 11757.0370417040. The cubic root of 138227920 is about 517.0492640746.

The spelling of 138227920 in words is "one hundred thirty-eight million, two hundred twenty-seven thousand, nine hundred twenty".