138892891 has 4 divisors (see below), whose sum is σ = 139265632. Its totient is φ = 138520152.

The previous prime is 138892889. The next prime is 138892909. The reversal of 138892891 is 198298831.

138892891 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 198298831 = 11467 ⋅17293.

It is a cyclic number.

It is not a de Polignac number, because 138892891 - 2¹ = 138892889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138892801) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 185811 + ... + 186556.

It is an arithmetic number, because the mean of its divisors is an integer number (34816408).

Almost surely, 2^138892891 is an apocalyptic number.

138892891 is a deficient number, since it is larger than the sum of its proper divisors (372741).

138892891 is an equidigital number, since it uses as much as digits as its factorization.

138892891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 372740.

The product of its digits is 248832, while the sum is 49.

The square root of 138892891 is about 11785.2828137470. The cubic root of 138892891 is about 517.8770584738.

The spelling of 138892891 in words is "one hundred thirty-eight million, eight hundred ninety-two thousand, eight hundred ninety-one".