21422200421 has 4 divisors (see below), whose sum is σ = 21423000492. Its totient is φ = 21421400352.

The previous prime is 21422200403. The next prime is 21422200507. The reversal of 21422200421 is 12400222412.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 10162656100 + 11259544321 = 100810^2 + 106111^2 .

It is a cyclic number.

It is not a de Polignac number, because 21422200421 - 2²² = 21418006117 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21422200393 and 21422200402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21422202421) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 358430 + ... + 413903.

It is an arithmetic number, because the mean of its divisors is an integer number (5355750123).

Almost surely, 2^21422200421 is an apocalyptic number.

It is an amenable number.

21422200421 is a deficient number, since it is larger than the sum of its proper divisors (800071).

21422200421 is an equidigital number, since it uses as much as digits as its factorization.

21422200421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 800070.

The product of its (nonzero) digits is 512, while the sum is 20.

Adding to 21422200421 its reverse (12400222412), we get a palindrome (33822422833).

The spelling of 21422200421 in words is "twenty-one billion, four hundred twenty-two million, two hundred thousand, four hundred twenty-one".