72428225 has 12 divisors (see below), whose sum is σ = 92908860. Its totient is φ = 55944000.

The previous prime is 72428221. The next prime is 72428243. The reversal of 72428225 is 52282427.

It can be written as a sum of positive squares in 6 ways, for example, as 2337841 + 70090384 = 1529^2 + 8372^2 .

It is not a de Polignac number, because 72428225 - 2² = 72428221 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 72428191 and 72428200.

It is not an unprimeable number, because it can be changed into a prime (72428221) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 49226 + ... + 50675.

It is an arithmetic number, because the mean of its divisors is an integer number (7742405).

Almost surely, 2^72428225 is an apocalyptic number.

It is an amenable number.

72428225 is a deficient number, since it is larger than the sum of its proper divisors (20480635).

72428225 is a wasteful number, since it uses less digits than its factorization.

72428225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99940 (or 99935 counting only the distinct ones).

The product of its digits is 17920, while the sum is 32.

The square root of 72428225 is about 8510.4773661646. The cubic root of 72428225 is about 416.8398977462.

The spelling of 72428225 in words is "seventy-two million, four hundred twenty-eight thousand, two hundred twenty-five".