21354550421401 has 2 divisors, whose sum is σ = 21354550421402. Its totient is φ = 21354550421400.

The previous prime is 21354550421389. The next prime is 21354550421419. The reversal of 21354550421401 is 10412405545312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17180394965776 + 4174155455625 = 4144924^2 + 2043075^2 .

It is a cyclic number.

It is not a de Polignac number, because 21354550421401 - 2¹⁹ = 21354549897113 is a prime.

It is not a weakly prime, because it can be changed into another prime (21354550424401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10677275210700 + 10677275210701.

It is an arithmetic number, because the mean of its divisors is an integer number (10677275210701).

Almost surely, 2^{21354550421401} is an apocalyptic number.

It is an amenable number.

21354550421401 is a deficient number, since it is larger than the sum of its proper divisors (1).

21354550421401 is an equidigital number, since it uses as much as digits as its factorization.

21354550421401 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96000, while the sum is 37.

Adding to 21354550421401 its reverse (10412405545312), we get a palindrome (31766955966713).

The spelling of 21354550421401 in words is "twenty-one trillion, three hundred fifty-four billion, five hundred fifty million, four hundred twenty-one thousand, four hundred one".