21142220009 has 2 divisors, whose sum is σ = 21142220010. Its totient is φ = 21142220008.

The previous prime is 21142220003. The next prime is 21142220027. The reversal of 21142220009 is 90002224112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20850493609 + 291726400 = 144397^2 + 17080^2 .

It is a cyclic number.

It is not a de Polignac number, because 21142220009 - 2²⁸ = 20873784553 is a prime.

It is not a weakly prime, because it can be changed into another prime (21142220003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10571110004 + 10571110005.

It is an arithmetic number, because the mean of its divisors is an integer number (10571110005).

Almost surely, 2^21142220009 is an apocalyptic number.

It is an amenable number.

21142220009 is a deficient number, since it is larger than the sum of its proper divisors (1).

21142220009 is an equidigital number, since it uses as much as digits as its factorization.

21142220009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 576, while the sum is 23.

The spelling of 21142220009 in words is "twenty-one billion, one hundred forty-two million, two hundred twenty thousand, nine".