21722454409 has 2 divisors, whose sum is σ = 21722454410. Its totient is φ = 21722454408.

The previous prime is 21722454389. The next prime is 21722454419. The reversal of 21722454409 is 90445422712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21178398784 + 544055625 = 145528^2 + 23325^2 .

It is a cyclic number.

It is not a de Polignac number, because 21722454409 - 2⁹ = 21722453897 is a prime.

It is not a weakly prime, because it can be changed into another prime (21722454419) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10861227204 + 10861227205.

It is an arithmetic number, because the mean of its divisors is an integer number (10861227205).

Almost surely, 2^21722454409 is an apocalyptic number.

It is an amenable number.

21722454409 is a deficient number, since it is larger than the sum of its proper divisors (1).

21722454409 is an equidigital number, since it uses as much as digits as its factorization.

21722454409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 161280, while the sum is 40.

The spelling of 21722454409 in words is "twenty-one billion, seven hundred twenty-two million, four hundred fifty-four thousand, four hundred nine".