1305489673 has 4 divisors (see below), whose sum is σ = 1305563908. Its totient is φ = 1305415440.

The previous prime is 1305489641. The next prime is 1305489739. The reversal of 1305489673 is 3769845031.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 21557449 + 1283932224 = 4643^2 + 35832^2 .

It is a cyclic number.

It is not a de Polignac number, because 1305489673 - 2⁵ = 1305489641 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1305489623) 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, 5815 + ... + 51427.

It is an arithmetic number, because the mean of its divisors is an integer number (326390977).

Almost surely, 2^1305489673 is an apocalyptic number.

It is an amenable number.

1305489673 is a deficient number, since it is larger than the sum of its proper divisors (74235).

1305489673 is an equidigital number, since it uses as much as digits as its factorization.

1305489673 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74234.

The product of its (nonzero) digits is 544320, while the sum is 46.

The square root of 1305489673 is about 36131.5606222593. The cubic root of 1305489673 is about 1092.9269795331.

The spelling of 1305489673 in words is "one billion, three hundred five million, four hundred eighty-nine thousand, six hundred seventy-three".