138433887 has 8 divisors (see below), whose sum is σ = 205087280. Its totient is φ = 92289240.

The previous prime is 138433877. The next prime is 138433901. The reversal of 138433887 is 788334831.

138433887 is a `hidden beast` number, since 138 + 433 + 8 + 87 = 666.

It is not a de Polignac number, because 138433887 - 2¹⁵ = 138401119 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138433837) 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, 2563564 + ... + 2563617.

It is an arithmetic number, because the mean of its divisors is an integer number (25635910).

Almost surely, 2^138433887 is an apocalyptic number.

138433887 is a deficient number, since it is larger than the sum of its proper divisors (66653393).

138433887 is an equidigital number, since it uses as much as digits as its factorization.

138433887 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5127190 (or 5127184 counting only the distinct ones).

The product of its digits is 387072, while the sum is 45.

The square root of 138433887 is about 11765.7930884407. The cubic root of 138433887 is about 517.3059469865.

The spelling of 138433887 in words is "one hundred thirty-eight million, four hundred thirty-three thousand, eight hundred eighty-seven".