321424021 has 2 divisors, whose sum is σ = 321424022. Its totient is φ = 321424020.

The previous prime is 321424003. The next prime is 321424039. The reversal of 321424021 is 120424123.

It is a balanced prime because it is at equal distance from previous prime (321424003) and next prime (321424039).

It can be written as a sum of positive squares in only one way, i.e., 258855921 + 62568100 = 16089^2 + 7910^2 .

It is a cyclic number.

It is not a de Polignac number, because 321424021 - 2¹¹ = 321421973 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 321424021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (321424421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160712010 + 160712011.

It is an arithmetic number, because the mean of its divisors is an integer number (160712011).

Almost surely, 2^321424021 is an apocalyptic number.

It is an amenable number.

321424021 is a deficient number, since it is larger than the sum of its proper divisors (1).

321424021 is an equidigital number, since it uses as much as digits as its factorization.

321424021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 384, while the sum is 19.

The square root of 321424021 is about 17928.3022341771. The cubic root of 321424021 is about 685.0034780579.

Adding to 321424021 its reverse (120424123), we get a palindrome (441848144).

It can be divided in two parts, 32142 and 4021, that added together give a palindrome (36163).

The spelling of 321424021 in words is "three hundred twenty-one million, four hundred twenty-four thousand, twenty-one".