3858757921 has 4 divisors (see below), whose sum is σ = 3872393392. Its totient is φ = 3845122452.

The previous prime is 3858757919. The next prime is 3858757933. The reversal of 3858757921 is 1297578583.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1297578583 = 7 ⋅185368369.

It is a cyclic number.

It is not a de Polignac number, because 3858757921 - 2¹ = 3858757919 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3858757901) 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, 6817311 + ... + 6817876.

It is an arithmetic number, because the mean of its divisors is an integer number (968098348).

Almost surely, 2^3858757921 is an apocalyptic number.

It is an amenable number.

3858757921 is a deficient number, since it is larger than the sum of its proper divisors (13635471).

3858757921 is a wasteful number, since it uses less digits than its factorization.

3858757921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13635470.

The product of its digits is 4233600, while the sum is 55.

The square root of 3858757921 is about 62118.9014793404. The cubic root of 3858757921 is about 1568.4927345280.

The spelling of 3858757921 in words is "three billion, eight hundred fifty-eight million, seven hundred fifty-seven thousand, nine hundred twenty-one".