3857661 has 6 divisors (see below), whose sum is σ = 5572190. Its totient is φ = 2571768.

The previous prime is 3857641. The next prime is 3857663. The reversal of 3857661 is 1667583.

It can be written as a sum of positive squares in only one way, i.e., 2232036 + 1625625 = 1494^2 + 1275^2 .

It is not a de Polignac number, because 3857661 - 2¹⁹ = 3333373 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 (3857663) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 214306 + ... + 214323.

Almost surely, 2^3857661 is an apocalyptic number.

It is an amenable number.

3857661 is a deficient number, since it is larger than the sum of its proper divisors (1714529).

3857661 is a wasteful number, since it uses less digits than its factorization.

3857661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 428635 (or 428632 counting only the distinct ones).

The product of its digits is 30240, while the sum is 36.

The square root of 3857661 is about 1964.0929204088. The cubic root of 3857661 is about 156.8344096399.

The spelling of 3857661 in words is "three million, eight hundred fifty-seven thousand, six hundred sixty-one".