138666288 has 40 divisors (see below), whose sum is σ = 360244800. Its totient is φ = 45961024.

The previous prime is 138666277. The next prime is 138666289. The reversal of 138666288 is 882666831.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (138666289) 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, 523 + ... + 16661.

It is an arithmetic number, because the mean of its divisors is an integer number (9006120).

Almost surely, 2^138666288 is an apocalyptic number.

It is an amenable number.

138666288 is an abundant number, since it is smaller than the sum of its proper divisors (221578512).

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

138666288 is a wasteful number, since it uses less digits than its factorization.

138666288 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16329 (or 16323 counting only the distinct ones).

The product of its digits is 663552, while the sum is 48.

The square root of 138666288 is about 11775.6650767589. The cubic root of 138666288 is about 517.5952672985.

The spelling of 138666288 in words is "one hundred thirty-eight million, six hundred sixty-six thousand, two hundred eighty-eight".