21222726149 has 2 divisors, whose sum is σ = 21222726150. Its totient is φ = 21222726148.

The previous prime is 21222726143. The next prime is 21222726163. The reversal of 21222726149 is 94162722212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19114998049 + 2107728100 = 138257^2 + 45910^2 .

It is a cyclic number.

It is not a de Polignac number, because 21222726149 - 2²⁰ = 21221677573 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21222726143) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10611363074 + 10611363075.

It is an arithmetic number, because the mean of its divisors is an integer number (10611363075).

Almost surely, 2^21222726149 is an apocalyptic number.

It is an amenable number.

21222726149 is a deficient number, since it is larger than the sum of its proper divisors (1).

21222726149 is an equidigital number, since it uses as much as digits as its factorization.

21222726149 is an evil number, because the sum of its binary digits is even.

The product of its digits is 48384, while the sum is 38.

The spelling of 21222726149 in words is "twenty-one billion, two hundred twenty-two million, seven hundred twenty-six thousand, one hundred forty-nine".