1421909 has 2 divisors, whose sum is σ = 1421910. Its totient is φ = 1421908.

The previous prime is 1421867. The next prime is 1421911. The reversal of 1421909 is 9091241.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1387684 + 34225 = 1178^2 + 185^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1421909 is a prime.

Together with 1421911, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1421969) 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, 710954 + 710955.

It is an arithmetic number, because the mean of its divisors is an integer number (710955).

2^1421909 is an apocalyptic number.

It is an amenable number.

1421909 is a deficient number, since it is larger than the sum of its proper divisors (1).

1421909 is an equidigital number, since it uses as much as digits as its factorization.

1421909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 648, while the sum is 26.

The square root of 1421909 is about 1192.4382583597. The cubic root of 1421909 is about 112.4494324178.

The spelling of 1421909 in words is "one million, four hundred twenty-one thousand, nine hundred nine".