3128661 has 6 divisors (see below), whose sum is σ = 4519190. Its totient is φ = 2085768.

The previous prime is 3128659. The next prime is 3128687. The reversal of 3128661 is 1668213.

It can be written as a sum of positive squares in only one way, i.e., 1703025 + 1425636 = 1305^2 + 1194^2 .

It is not a de Polignac number, because 3128661 - 2¹ = 3128659 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 (3128611) 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, 173806 + ... + 173823.

Almost surely, 2^3128661 is an apocalyptic number.

It is an amenable number.

3128661 is a deficient number, since it is larger than the sum of its proper divisors (1390529).

3128661 is a wasteful number, since it uses less digits than its factorization.

3128661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 347635 (or 347632 counting only the distinct ones).

The product of its digits is 1728, while the sum is 27.

The square root of 3128661 is about 1768.8021370408. The cubic root of 3128661 is about 146.2579570512.

The spelling of 3128661 in words is "three million, one hundred twenty-eight thousand, six hundred sixty-one".