21236287229 has 2 divisors, whose sum is σ = 21236287230. Its totient is φ = 21236287228.

The previous prime is 21236287187. The next prime is 21236287271. The reversal of 21236287229 is 92278263212.

It is a balanced prime because it is at equal distance from previous prime (21236287187) and next prime (21236287271).

It can be written as a sum of positive squares in only one way, i.e., 17976105625 + 3260181604 = 134075^2 + 57098^2 .

It is a cyclic number.

It is not a de Polignac number, because 21236287229 - 2³² = 16941319933 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21236287229.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21236287829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10618143614 + 10618143615.

It is an arithmetic number, because the mean of its divisors is an integer number (10618143615).

Almost surely, 2^21236287229 is an apocalyptic number.

It is an amenable number.

21236287229 is a deficient number, since it is larger than the sum of its proper divisors (1).

21236287229 is an equidigital number, since it uses as much as digits as its factorization.

21236287229 is an evil number, because the sum of its binary digits is even.

The product of its digits is 290304, while the sum is 44.

The spelling of 21236287229 in words is "twenty-one billion, two hundred thirty-six million, two hundred eighty-seven thousand, two hundred twenty-nine".