225143765621 has 4 divisors (see below), whose sum is σ = 225326959500. Its totient is φ = 224960571744.

The previous prime is 225143765599. The next prime is 225143765641. The reversal of 225143765621 is 126567341522.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 126567341522 = 2 ⋅63283670761.

It can be written as a sum of positive squares in 2 ways, for example, as 108392392900 + 116751372721 = 329230^2 + 341689^2 .

It is a cyclic number.

It is not a de Polignac number, because 225143765621 - 2¹⁰ = 225143764597 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (225143765641) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 91595096 + ... + 91597553.

It is an arithmetic number, because the mean of its divisors is an integer number (56331739875).

Almost surely, 2^225143765621 is an apocalyptic number.

It is an amenable number.

225143765621 is a deficient number, since it is larger than the sum of its proper divisors (183193879).

225143765621 is a wasteful number, since it uses less digits than its factorization.

225143765621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 183193878.

The product of its digits is 604800, while the sum is 44.

The spelling of 225143765621 in words is "two hundred twenty-five billion, one hundred forty-three million, seven hundred sixty-five thousand, six hundred twenty-one".