1145312521 has 4 divisors (see below), whose sum is σ = 1145417344. Its totient is φ = 1145207700.

The previous prime is 1145312513. The next prime is 1145312537. The reversal of 1145312521 is 1252135411.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 1252135411 = 223 ⋅5614957.

It is a cyclic number.

It is not a de Polignac number, because 1145312521 - 2³ = 1145312513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1145312561) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33825 + ... + 58606.

It is an arithmetic number, because the mean of its divisors is an integer number (286354336).

Almost surely, 2^1145312521 is an apocalyptic number.

It is an amenable number.

1145312521 is a deficient number, since it is larger than the sum of its proper divisors (104823).

1145312521 is an equidigital number, since it uses as much as digits as its factorization.

1145312521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 104822.

The product of its digits is 1200, while the sum is 25.

The square root of 1145312521 is about 33842.4662369633. The cubic root of 1145312521 is about 1046.2641298425.

Adding to 1145312521 its reverse (1252135411), we get a palindrome (2397447932).

The spelling of 1145312521 in words is "one billion, one hundred forty-five million, three hundred twelve thousand, five hundred twenty-one".