21342310421 has 2 divisors, whose sum is σ = 21342310422. Its totient is φ = 21342310420.

The previous prime is 21342310411. The next prime is 21342310433. The reversal of 21342310421 is 12401324312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20860024900 + 482285521 = 144430^2 + 21961^2 .

It is a cyclic number.

It is not a de Polignac number, because 21342310421 - 2²⁶ = 21275201557 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21342310411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10671155210 + 10671155211.

It is an arithmetic number, because the mean of its divisors is an integer number (10671155211).

Almost surely, 2^21342310421 is an apocalyptic number.

It is an amenable number.

21342310421 is a deficient number, since it is larger than the sum of its proper divisors (1).

21342310421 is an equidigital number, since it uses as much as digits as its factorization.

21342310421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1152, while the sum is 23.

Adding to 21342310421 its reverse (12401324312), we get a palindrome (33743634733).

The spelling of 21342310421 in words is "twenty-one billion, three hundred forty-two million, three hundred ten thousand, four hundred twenty-one".