225021665461 has 2 divisors, whose sum is σ = 225021665462. Its totient is φ = 225021665460.

The previous prime is 225021665437. The next prime is 225021665509. The reversal of 225021665461 is 164566120522.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 177620102500 + 47401562961 = 421450^2 + 217719^2 .

It is a cyclic number.

It is not a de Polignac number, because 225021665461 - 2¹⁷ = 225021534389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (225021665411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 112510832730 + 112510832731.

It is an arithmetic number, because the mean of its divisors is an integer number (112510832731).

Almost surely, 2^225021665461 is an apocalyptic number.

It is an amenable number.

225021665461 is a deficient number, since it is larger than the sum of its proper divisors (1).

225021665461 is an equidigital number, since it uses as much as digits as its factorization.

225021665461 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 172800, while the sum is 40.

Adding to 225021665461 its reverse (164566120522), we get a palindrome (389587785983).

The spelling of 225021665461 in words is "two hundred twenty-five billion, twenty-one million, six hundred sixty-five thousand, four hundred sixty-one".