38685821 has 4 divisors (see below), whose sum is σ = 38754144. Its totient is φ = 38617500.

The previous prime is 38685809. The next prime is 38685827. The reversal of 38685821 is 12858683.

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 a de Polignac number, because none of the positive numbers 2^k-38685821 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 (38685827) 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, 33305 + ... + 34446.

It is an arithmetic number, because the mean of its divisors is an integer number (9688536).

Almost surely, 2^38685821 is an apocalyptic number.

It is an amenable number.

38685821 is a deficient number, since it is larger than the sum of its proper divisors (68323).

38685821 is an equidigital number, since it uses as much as digits as its factorization.

38685821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68322.

The product of its digits is 92160, while the sum is 41.

The square root of 38685821 is about 6219.7926814324. The cubic root of 38685821 is about 338.2080491479.

The spelling of 38685821 in words is "thirty-eight million, six hundred eighty-five thousand, eight hundred twenty-one".