21433240109 has 2 divisors, whose sum is σ = 21433240110. Its totient is φ = 21433240108.

The previous prime is 21433240061. The next prime is 21433240151. The reversal of 21433240109 is 90104233412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20729664484 + 703575625 = 143978^2 + 26525^2 .

It is a cyclic number.

It is not a de Polignac number, because 21433240109 - 2⁸ = 21433239853 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21433240159) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10716620054 + 10716620055.

It is an arithmetic number, because the mean of its divisors is an integer number (10716620055).

Almost surely, 2^21433240109 is an apocalyptic number.

It is an amenable number.

21433240109 is a deficient number, since it is larger than the sum of its proper divisors (1).

21433240109 is an equidigital number, since it uses as much as digits as its factorization.

21433240109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5184, while the sum is 29.

The spelling of 21433240109 in words is "twenty-one billion, four hundred thirty-three million, two hundred forty thousand, one hundred nine".