138897813 has 8 divisors (see below), whose sum is σ = 185316768. Its totient is φ = 92538704.

The previous prime is 138897799. The next prime is 138897823. The reversal of 138897813 is 318798831.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 138897813 - 2⁶ = 138897749 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138897823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9231 + ... + 19052.

It is an arithmetic number, because the mean of its divisors is an integer number (23164596).

Almost surely, 2^138897813 is an apocalyptic number.

It is an amenable number.

138897813 is a deficient number, since it is larger than the sum of its proper divisors (46418955).

138897813 is a wasteful number, since it uses less digits than its factorization.

138897813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29923.

The product of its digits is 290304, while the sum is 48.

The square root of 138897813 is about 11785.4916316631. The cubic root of 138897813 is about 517.8831758033.

The spelling of 138897813 in words is "one hundred thirty-eight million, eight hundred ninety-seven thousand, eight hundred thirteen".