1401809 has 2 divisors, whose sum is σ = 1401810. Its totient is φ = 1401808.

The previous prime is 1401793. The next prime is 1401811. The reversal of 1401809 is 9081041.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1392400 + 9409 = 1180^2 + 97^2 .

It is a cyclic number.

It is not a de Polignac number, because 1401809 - 2⁴ = 1401793 is a prime.

Together with 1401811, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1401409) 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, 700904 + 700905.

It is an arithmetic number, because the mean of its divisors is an integer number (700905).

2^1401809 is an apocalyptic number.

It is an amenable number.

1401809 is a deficient number, since it is larger than the sum of its proper divisors (1).

1401809 is an equidigital number, since it uses as much as digits as its factorization.

1401809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 288, while the sum is 23.

The square root of 1401809 is about 1183.9801518607. The cubic root of 1401809 is about 111.9170570006.

The spelling of 1401809 in words is "one million, four hundred one thousand, eight hundred nine".