1215445225 has 12 divisors (see below), whose sum is σ = 1509480396. Its totient is φ = 970854080.

The previous prime is 1215445223. The next prime is 1215445229. The reversal of 1215445225 is 5225445121.

It can be written as a sum of positive squares in 6 ways, for example, as 218211984 + 997233241 = 14772^2 + 31579^2 .

It is not a de Polignac number, because 1215445225 - 2¹ = 1215445223 is a prime.

It is a super-3 number, since 3×1215445225³ (a number of 28 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1215445223) 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, 20902 + ... + 53551.

It is an arithmetic number, because the mean of its divisors is an integer number (125790033).

Almost surely, 2^1215445225 is an apocalyptic number.

It is an amenable number.

1215445225 is a deficient number, since it is larger than the sum of its proper divisors (294035171).

1215445225 is an equidigital number, since it uses as much as digits as its factorization.

1215445225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75116 (or 75111 counting only the distinct ones).

The product of its digits is 16000, while the sum is 31.

The square root of 1215445225 is about 34863.2360087241. The cubic root of 1215445225 is about 1067.1983143451.

The spelling of 1215445225 in words is "one billion, two hundred fifteen million, four hundred forty-five thousand, two hundred twenty-five".