1670661 has 24 divisors (see below), whose sum is σ = 2578680. Its totient is φ = 1040256.

The previous prime is 1670659. The next prime is 1670687. The reversal of 1670661 is 1660761.

It can be written as a sum of positive squares in 4 ways, for example, as 980100 + 690561 = 990^2 + 831^2 .

It is not a de Polignac number, because 1670661 - 2¹ = 1670659 is a prime.

It is a super-2 number, since 2×1670661² = 5582216353842, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1670161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9571 + ... + 9743.

It is an arithmetic number, because the mean of its divisors is an integer number (107445).

2^1670661 is an apocalyptic number.

It is an amenable number.

1670661 is a deficient number, since it is larger than the sum of its proper divisors (908019).

1670661 is a wasteful number, since it uses less digits than its factorization.

1670661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 245 (or 242 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 27.

The square root of 1670661 is about 1292.5405216085. The cubic root of 1670661 is about 118.6577507013.

The spelling of 1670661 in words is "one million, six hundred seventy thousand, six hundred sixty-one".