72212225 has 6 divisors (see below), whose sum is σ = 89543190. Its totient is φ = 57769760.

The previous prime is 72212213. The next prime is 72212279. The reversal of 72212225 is 52221227.

72212225 = 944² + 945² + ... + 1018².

It can be written as a sum of positive squares in 3 ways, for example, as 5740816 + 66471409 = 2396^2 + 8153^2 .

It is not a de Polignac number, because 72212225 - 2¹⁰ = 72211201 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 72212225.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1444220 + ... + 1444269.

It is an arithmetic number, because the mean of its divisors is an integer number (14923865).

Almost surely, 2^72212225 is an apocalyptic number.

It is an amenable number.

72212225 is a deficient number, since it is larger than the sum of its proper divisors (17330965).

72212225 is a wasteful number, since it uses less digits than its factorization.

72212225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2888499 (or 2888494 counting only the distinct ones).

The product of its digits is 1120, while the sum is 23.

The square root of 72212225 is about 8497.7776506567. Note that the first 3 decimals coincide. The cubic root of 72212225 is about 416.4251097655.

It can be divided in two parts, 7221222 and 5, that added together give a palindrome (7221227).

The spelling of 72212225 in words is "seventy-two million, two hundred twelve thousand, two hundred twenty-five".