225647729 has 4 divisors (see below), whose sum is σ = 232926720. Its totient is φ = 218368740.

The previous prime is 225647717. The next prime is 225647731. The reversal of 225647729 is 927746522.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 927746522 = 2 ⋅463873261.

It is a cyclic number.

It is not a de Polignac number, because 225647729 - 2⁸ = 225647473 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 225647729.

It is not an unprimeable number, because it can be changed into a prime (225644729) 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, 3639449 + ... + 3639510.

It is an arithmetic number, because the mean of its divisors is an integer number (58231680).

Almost surely, 2^225647729 is an apocalyptic number.

It is an amenable number.

225647729 is a deficient number, since it is larger than the sum of its proper divisors (7278991).

225647729 is an equidigital number, since it uses as much as digits as its factorization.

225647729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7278990.

The product of its digits is 423360, while the sum is 44.

The square root of 225647729 is about 15021.5754499986. The cubic root of 225647729 is about 608.8032875868.

The spelling of 225647729 in words is "two hundred twenty-five million, six hundred forty-seven thousand, seven hundred twenty-nine".