1670891 has 2 divisors, whose sum is σ = 1670892. Its totient is φ = 1670890.

The previous prime is 1670887. The next prime is 1670899. The reversal of 1670891 is 1980761.

It is a weak prime.

It is an emirp because it is prime and its reverse (1980761) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1670891 - 2² = 1670887 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (1670899) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 835445 + 835446.

It is an arithmetic number, because the mean of its divisors is an integer number (835446).

2^1670891 is an apocalyptic number.

1670891 is a deficient number, since it is larger than the sum of its proper divisors (1).

1670891 is an equidigital number, since it uses as much as digits as its factorization.

1670891 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3024, while the sum is 32.

The square root of 1670891 is about 1292.6294906121. The cubic root of 1670891 is about 118.6631956580.

It can be divided in two parts, 16 and 70891, that added together give a palindrome (70907).

The spelling of 1670891 in words is "one million, six hundred seventy thousand, eight hundred ninety-one".