21225120529 has 2 divisors, whose sum is σ = 21225120530. Its totient is φ = 21225120528.

The previous prime is 21225120451. The next prime is 21225120557. The reversal of 21225120529 is 92502152212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12802469904 + 8422650625 = 113148^2 + 91775^2 .

It is a cyclic number.

It is not a de Polignac number, because 21225120529 - 2⁷ = 21225120401 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21225120529.

It is not a weakly prime, because it can be changed into another prime (21225120029) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10612560264 + 10612560265.

It is an arithmetic number, because the mean of its divisors is an integer number (10612560265).

Almost surely, 2^21225120529 is an apocalyptic number.

It is an amenable number.

21225120529 is a deficient number, since it is larger than the sum of its proper divisors (1).

21225120529 is an equidigital number, since it uses as much as digits as its factorization.

21225120529 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7200, while the sum is 31.

The spelling of 21225120529 in words is "twenty-one billion, two hundred twenty-five million, one hundred twenty thousand, five hundred twenty-nine".