1421891321 has 2 divisors, whose sum is σ = 1421891322. Its totient is φ = 1421891320.

The previous prime is 1421891309. The next prime is 1421891347. The reversal of 1421891321 is 1231981241.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 983449600 + 438441721 = 31360^2 + 20939^2 .

It is an emirp because it is prime and its reverse (1231981241) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1421891321 - 2¹⁸ = 1421629177 is a prime.

It is not a weakly prime, because it can be changed into another prime (1421891371) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 710945660 + 710945661.

It is an arithmetic number, because the mean of its divisors is an integer number (710945661).

Almost surely, 2^1421891321 is an apocalyptic number.

It is an amenable number.

1421891321 is a deficient number, since it is larger than the sum of its proper divisors (1).

1421891321 is an equidigital number, since it uses as much as digits as its factorization.

1421891321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3456, while the sum is 32.

The square root of 1421891321 is about 37707.9742362275. The cubic root of 1421891321 is about 1124.4896637729.

The spelling of 1421891321 in words is "one billion, four hundred twenty-one million, eight hundred ninety-one thousand, three hundred twenty-one".