1421621 has 2 divisors, whose sum is σ = 1421622. Its totient is φ = 1421620.

The previous prime is 1421611. The next prime is 1421627. The reversal of 1421621 is 1261241.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1240996 + 180625 = 1114^2 + 425^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1421621 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1421621.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1421627) 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, 710810 + 710811.

It is an arithmetic number, because the mean of its divisors is an integer number (710811).

2^1421621 is an apocalyptic number.

It is an amenable number.

1421621 is a deficient number, since it is larger than the sum of its proper divisors (1).

1421621 is an equidigital number, since it uses as much as digits as its factorization.

1421621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 96, while the sum is 17.

The square root of 1421621 is about 1192.3174912749. The cubic root of 1421621 is about 112.4418398965.

Adding to 1421621 its reverse (1261241), we get a palindrome (2682862).

The spelling of 1421621 in words is "one million, four hundred twenty-one thousand, six hundred twenty-one".