138882681 has 20 divisors (see below), whose sum is σ = 237105792. Its totient is φ = 79361208.

The previous prime is 138882659. The next prime is 138882691. The reversal of 138882681 is 186288831.

138882681 is a `hidden beast` number, since 1 + 388 + 8 + 268 + 1 = 666.

138882681 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 138882681 - 2¹⁰ = 138881657 is a prime.

It is a super-2 number, since 2×138882681² = 38576798163495522, which contains 22 as substring.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (138882641) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 121905 + ... + 123038.

Almost surely, 2^138882681 is an apocalyptic number.

It is an amenable number.

138882681 is a deficient number, since it is larger than the sum of its proper divisors (98223111).

138882681 is an equidigital number, since it uses as much as digits as its factorization.

138882681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 244962 (or 244953 counting only the distinct ones).

The product of its digits is 147456, while the sum is 45.

The square root of 138882681 is about 11784.8496384129. The cubic root of 138882681 is about 517.8643684690.

The spelling of 138882681 in words is "one hundred thirty-eight million, eight hundred eighty-two thousand, six hundred eighty-one".