3870208521 has 27 divisors (see below), whose sum is σ = 5678188789. Its totient is φ = 2540199552.

The previous prime is 3870208493. The next prime is 3870208523. The reversal of 3870208521 is 1258020783.

The square root of 3870208521 is 62211.

It is a perfect power (a square), and thus also a powerful number.

3870208521 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 1416393225 + 2453815296 = 37635^2 + 49536^2 .

It is not a de Polignac number, because 3870208521 - 2³¹ = 1722724873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3870208523) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 16610221 + ... + 16610453.

Almost surely, 2^3870208521 is an apocalyptic number.

3870208521 is the 62211-st square number.

3870208521 is the 31106-th centered octagonal number.

It is an amenable number.

3870208521 is a deficient number, since it is larger than the sum of its proper divisors (1807980268).

3870208521 is an frugal number, since it uses more digits than its factorization.

3870208521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 650 (or 325 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 36.

The cubic root of 3870208521 is about 1570.0426673733.

Multiplying 3870208521 by its sum of digits (36), we get a square (139327506756 = 373266²).

The spelling of 3870208521 in words is "three billion, eight hundred seventy million, two hundred eight thousand, five hundred twenty-one".