3903661 has 4 divisors (see below), whose sum is σ = 4038300. Its totient is φ = 3769024.

The previous prime is 3903649. The next prime is 3903667. The reversal of 3903661 is 1663093.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1663093 = 17 ⋅97829.

It can be written as a sum of positive squares in 2 ways, for example, as 2449225 + 1454436 = 1565^2 + 1206^2 .

It is a cyclic number.

It is not a de Polignac number, because 3903661 - 2⁷ = 3903533 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 (3903667) 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, 67276 + ... + 67333.

It is an arithmetic number, because the mean of its divisors is an integer number (1009575).

Almost surely, 2^3903661 is an apocalyptic number.

It is an amenable number.

3903661 is a deficient number, since it is larger than the sum of its proper divisors (134639).

3903661 is a wasteful number, since it uses less digits than its factorization.

3903661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134638.

The product of its (nonzero) digits is 2916, while the sum is 28.

The square root of 3903661 is about 1975.7684580942. The cubic root of 3903661 is about 157.4553295673.

The spelling of 3903661 in words is "three million, nine hundred three thousand, six hundred sixty-one".