1321023545 has 12 divisors (see below), whose sum is σ = 1673054820. Its totient is φ = 1001195424.

The previous prime is 1321023527. The next prime is 1321023547. The reversal of 1321023545 is 5453201231.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 191324224 + 1129699321 = 13832^2 + 33611^2 .

It is not a de Polignac number, because 1321023545 - 2¹² = 1321019449 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1321023547) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 364130 + ... + 367739.

It is an arithmetic number, because the mean of its divisors is an integer number (139421235).

Almost surely, 2^1321023545 is an apocalyptic number.

It is an amenable number.

1321023545 is a deficient number, since it is larger than the sum of its proper divisors (352031275).

1321023545 is an equidigital number, since it uses as much as digits as its factorization.

1321023545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 731912 (or 731893 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 26.

The square root of 1321023545 is about 36345.8875940594. The cubic root of 1321023545 is about 1097.2447698757.

Adding to 1321023545 its reverse (5453201231), we get a palindrome (6774224776).

The spelling of 1321023545 in words is "one billion, three hundred twenty-one million, twenty-three thousand, five hundred forty-five".