1421989 has 2 divisors, whose sum is σ = 1421990. Its totient is φ = 1421988.

The previous prime is 1421977. The next prime is 1422007. The reversal of 1421989 is 9891241.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1399489 + 22500 = 1183^2 + 150^2 .

It is an emirp because it is prime and its reverse (9891241) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1421989 - 2¹⁵ = 1389221 is a prime.

It is a super-2 number, since 2×1421989² = 4044105432242, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1421909) 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, 710994 + 710995.

It is an arithmetic number, because the mean of its divisors is an integer number (710995).

2^1421989 is an apocalyptic number.

It is an amenable number.

1421989 is a deficient number, since it is larger than the sum of its proper divisors (1).

1421989 is an equidigital number, since it uses as much as digits as its factorization.

1421989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5184, while the sum is 34.

The square root of 1421989 is about 1192.4718026016. The cubic root of 1421989 is about 112.4515412696.

The spelling of 1421989 in words is "one million, four hundred twenty-one thousand, nine hundred eighty-nine".