38687881 has 4 divisors (see below), whose sum is σ = 38709252. Its totient is φ = 38666512.

The previous prime is 38687867. The next prime is 38687911. The reversal of 38687881 is 18878683.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18878683 = 599 ⋅31517.

It can be written as a sum of positive squares in 2 ways, for example, as 4862025 + 33825856 = 2205^2 + 5816^2 .

It is a cyclic number.

It is not a de Polignac number, because 38687881 - 2¹¹ = 38685833 is a prime.

It is a super-2 number, since 2×38687881² = 2993504272540322, which contains 22 as substring.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (38687821) 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, 7690 + ... + 11683.

It is an arithmetic number, because the mean of its divisors is an integer number (9677313).

Almost surely, 2^38687881 is an apocalyptic number.

It is an amenable number.

38687881 is a deficient number, since it is larger than the sum of its proper divisors (21371).

38687881 is a wasteful number, since it uses less digits than its factorization.

38687881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21370.

The product of its digits is 516096, while the sum is 49.

The square root of 38687881 is about 6219.9582796028. The cubic root of 38687881 is about 338.2140521760.

The spelling of 38687881 in words is "thirty-eight million, six hundred eighty-seven thousand, eight hundred eighty-one".