1340021 has 2 divisors, whose sum is σ = 1340022. Its totient is φ = 1340020.

The previous prime is 1340011. The next prime is 1340033. The reversal of 1340021 is 1200431.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 784996 + 555025 = 886^2 + 745^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1340021 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 1339984 and 1340011.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1340011) 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, 670010 + 670011.

It is an arithmetic number, because the mean of its divisors is an integer number (670011).

2^1340021 is an apocalyptic number.

It is an amenable number.

1340021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1340021 is an equidigital number, since it uses as much as digits as its factorization.

1340021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24, while the sum is 11.

The square root of 1340021 is about 1157.5927608620. The cubic root of 1340021 is about 110.2479530611.

Adding to 1340021 its reverse (1200431), we get a palindrome (2540452).

The spelling of 1340021 in words is "one million, three hundred forty thousand, twenty-one".