21423004211381 has 2 divisors, whose sum is σ = 21423004211382. Its totient is φ = 21423004211380.

The previous prime is 21423004211363. The next prime is 21423004211459. The reversal of 21423004211381 is 18311240032412.

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., 20408483880625 + 1014520330756 = 4517575^2 + 1007234^2 .

It is a cyclic number.

It is not a de Polignac number, because 21423004211381 - 2¹⁴ = 21423004194997 is a prime.

It is a super-2 number, since 2×21423004211381² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21423004211681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10711502105690 + 10711502105691.

It is an arithmetic number, because the mean of its divisors is an integer number (10711502105691).

Almost surely, 2^{21423004211381} is an apocalyptic number.

It is an amenable number.

21423004211381 is a deficient number, since it is larger than the sum of its proper divisors (1).

21423004211381 is an equidigital number, since it uses as much as digits as its factorization.

21423004211381 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9216, while the sum is 32.

Adding to 21423004211381 its reverse (18311240032412), we get a palindrome (39734244243793).

The spelling of 21423004211381 in words is "twenty-one trillion, four hundred twenty-three billion, four million, two hundred eleven thousand, three hundred eighty-one".