1225305221 has 12 divisors (see below), whose sum is σ = 1426567500. Its totient is φ = 1049368320.

The previous prime is 1225305203. The next prime is 1225305223. The reversal of 1225305221 is 1225035221.

It can be written as a sum of positive squares in 2 ways, for example, as 233937025 + 991368196 = 15295^2 + 31486^2 .

It is not a de Polignac number, because 1225305221 - 2⁶ = 1225305157 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 (1225305223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 51191 + ... + 71211.

It is an arithmetic number, because the mean of its divisors is an integer number (118880625).

Almost surely, 2^1225305221 is an apocalyptic number.

It is an amenable number.

1225305221 is a deficient number, since it is larger than the sum of its proper divisors (201262279).

1225305221 is a wasteful number, since it uses less digits than its factorization.

1225305221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21284 (or 21277 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 1225305221 is about 35004.3600284307. The cubic root of 1225305221 is about 1070.0763392124.

The spelling of 1225305221 in words is "one billion, two hundred twenty-five million, three hundred five thousand, two hundred twenty-one".