38999813 has 4 divisors (see below), whose sum is σ = 40053900. Its totient is φ = 37945728.

The previous prime is 38999797. The next prime is 38999843. The reversal of 38999813 is 31899983.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 31899983 = 181 ⋅176243.

It can be written as a sum of positive squares in 2 ways, for example, as 34128964 + 4870849 = 5842^2 + 2207^2 .

It is a cyclic number.

It is not a de Polignac number, because 38999813 - 2⁴ = 38999797 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 (38999843) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 526988 + ... + 527061.

It is an arithmetic number, because the mean of its divisors is an integer number (10013475).

Almost surely, 2^38999813 is an apocalyptic number.

It is an amenable number.

38999813 is a deficient number, since it is larger than the sum of its proper divisors (1054087).

38999813 is a wasteful number, since it uses less digits than its factorization.

38999813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1054086.

The product of its digits is 419904, while the sum is 50.

The square root of 38999813 is about 6244.9830263981. The cubic root of 38999813 is about 339.1206022864.

The spelling of 38999813 in words is "thirty-eight million, nine hundred ninety-nine thousand, eight hundred thirteen".