1691401 has 2 divisors, whose sum is σ = 1691402. Its totient is φ = 1691400.

The previous prime is 1691387. The next prime is 1691411. The reversal of 1691401 is 1041961.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1550025 + 141376 = 1245^2 + 376^2 .

It is an emirp because it is prime and its reverse (1041961) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1691401 - 2⁵ = 1691369 is a prime.

It is not a weakly prime, because it can be changed into another prime (1691411) 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 as a sum of consecutive naturals, namely, 845700 + 845701.

It is an arithmetic number, because the mean of its divisors is an integer number (845701).

2^1691401 is an apocalyptic number.

It is an amenable number.

1691401 is a deficient number, since it is larger than the sum of its proper divisors (1).

1691401 is an equidigital number, since it uses as much as digits as its factorization.

1691401 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 216, while the sum is 22.

The square root of 1691401 is about 1300.5387345250. The cubic root of 1691401 is about 119.1467483186.

The spelling of 1691401 in words is "one million, six hundred ninety-one thousand, four hundred one".