138890813 has 4 divisors (see below), whose sum is σ = 144929568. Its totient is φ = 132852060.

The previous prime is 138890803. The next prime is 138890827. The reversal of 138890813 is 318098831.

It is a happy number.

138890813 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 a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 318098831 = 7561 ⋅42071.

It is a cyclic number.

It is not a de Polignac number, because 138890813 - 2¹⁰ = 138889789 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 (138890803) 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, 3019343 + ... + 3019388.

It is an arithmetic number, because the mean of its divisors is an integer number (36232392).

Almost surely, 2^138890813 is an apocalyptic number.

It is an amenable number.

138890813 is a deficient number, since it is larger than the sum of its proper divisors (6038755).

138890813 is an equidigital number, since it uses as much as digits as its factorization.

138890813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6038754.

The product of its (nonzero) digits is 41472, while the sum is 41.

The square root of 138890813 is about 11785.1946526139. The cubic root of 138890813 is about 517.8744757788.

The spelling of 138890813 in words is "one hundred thirty-eight million, eight hundred ninety thousand, eight hundred thirteen".