38666809 has 4 divisors (see below), whose sum is σ = 38687616. Its totient is φ = 38646004.

The previous prime is 38666807. The next prime is 38666821. The reversal of 38666809 is 90866683.

It is a happy number.

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.

It is a cyclic number.

It is not a de Polignac number, because 38666809 - 2¹ = 38666807 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (38666807) 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, 7309 + ... + 11434.

It is an arithmetic number, because the mean of its divisors is an integer number (9671904).

Almost surely, 2^38666809 is an apocalyptic number.

It is an amenable number.

38666809 is a deficient number, since it is larger than the sum of its proper divisors (20807).

38666809 is a wasteful number, since it uses less digits than its factorization.

38666809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20806.

The product of its (nonzero) digits is 373248, while the sum is 46.

The square root of 38666809 is about 6218.2641468500. The cubic root of 38666809 is about 338.1526363818.

The spelling of 38666809 in words is "thirty-eight million, six hundred sixty-six thousand, eight hundred nine".