3661640 has 16 divisors (see below), whose sum is σ = 8238780. Its totient is φ = 1464640.

The previous prime is 3661633. The next prime is 3661643. The reversal of 3661640 is 461663.

3661640 is nontrivially palindromic in base 6.

It can be written as a sum of positive squares in 2 ways, for example, as 3541924 + 119716 = 1882^2 + 346^2 .

It is not an unprimeable number, because it can be changed into a prime (3661643) 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, 45731 + ... + 45810.

Almost surely, 2^3661640 is an apocalyptic number.

It is an amenable number.

3661640 is an abundant number, since it is smaller than the sum of its proper divisors (4577140).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

3661640 is a wasteful number, since it uses less digits than its factorization.

3661640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91552 (or 91548 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 26.

The square root of 3661640 is about 1913.5412198330. The cubic root of 3661640 is about 154.1316690300.

The spelling of 3661640 in words is "three million, six hundred sixty-one thousand, six hundred forty".