225021670021 has 2 divisors, whose sum is σ = 225021670022. Its totient is φ = 225021670020.

The previous prime is 225021669997. The next prime is 225021670051. The reversal of 225021670021 is 120076120522.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 145996589025 + 79025080996 = 382095^2 + 281114^2 .

It is a cyclic number.

It is not a de Polignac number, because 225021670021 - 2⁷ = 225021669893 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (225021670051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 112510835010 + 112510835011.

It is an arithmetic number, because the mean of its divisors is an integer number (112510835011).

Almost surely, 2^225021670021 is an apocalyptic number.

It is an amenable number.

225021670021 is a deficient number, since it is larger than the sum of its proper divisors (1).

225021670021 is an equidigital number, since it uses as much as digits as its factorization.

225021670021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3360, while the sum is 28.

Adding to 225021670021 its reverse (120076120522), we get a palindrome (345097790543).

The spelling of 225021670021 in words is "two hundred twenty-five billion, twenty-one million, six hundred seventy thousand, twenty-one".