1151445221 has 4 divisors (see below), whose sum is σ = 1156223244. Its totient is φ = 1146667200.

The previous prime is 1151445209. The next prime is 1151445223. The reversal of 1151445221 is 1225441511.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1225441511 = 7 ⋅175063073.

It can be written as a sum of positive squares in 2 ways, for example, as 373648900 + 777796321 = 19330^2 + 27889^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1151445221 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 (1151445223) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 2388650 + ... + 2389131.

It is an arithmetic number, because the mean of its divisors is an integer number (289055811).

Almost surely, 2^1151445221 is an apocalyptic number.

It is an amenable number.

1151445221 is a deficient number, since it is larger than the sum of its proper divisors (4778023).

1151445221 is an equidigital number, since it uses as much as digits as its factorization.

1151445221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4778022.

The product of its digits is 1600, while the sum is 26.

The square root of 1151445221 is about 33932.9518462512. The cubic root of 1151445221 is about 1048.1282514629.

Adding to 1151445221 its reverse (1225441511), we get a palindrome (2376886732).

The spelling of 1151445221 in words is "one billion, one hundred fifty-one million, four hundred forty-five thousand, two hundred twenty-one".