3870521 has 8 divisors (see below), whose sum is σ = 3953160. Its totient is φ = 3788928.

The previous prime is 3870499. The next prime is 3870527. The reversal of 3870521 is 1250783.

It can be written as a sum of positive squares in 4 ways, for example, as 13225 + 3857296 = 115^2 + 1964^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 3870521 - 2⁶ = 3870457 is a prime.

It is a super-2 number, since 2×3870521² = 29961865622882, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3870527) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13835 + ... + 14111.

It is an arithmetic number, because the mean of its divisors is an integer number (494145).

Almost surely, 2^3870521 is an apocalyptic number.

It is an amenable number.

3870521 is a deficient number, since it is larger than the sum of its proper divisors (82639).

3870521 is a wasteful number, since it uses less digits than its factorization.

3870521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 523.

The product of its (nonzero) digits is 1680, while the sum is 26.

The square root of 3870521 is about 1967.3639724260. The cubic root of 3870521 is about 157.0084921097.

The spelling of 3870521 in words is "three million, eight hundred seventy thousand, five hundred twenty-one".