1320428723 has 4 divisors (see below), whose sum is σ = 1322026200. Its totient is φ = 1318831248.

The previous prime is 1320428719. The next prime is 1320428741. The reversal of 1320428723 is 3278240231.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1320428723 - 2² = 1320428719 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1320428723.

It is not an unprimeable number, because it can be changed into a prime (1320428323) 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, 797498 + ... + 799151.

It is an arithmetic number, because the mean of its divisors is an integer number (330506550).

Almost surely, 2^1320428723 is an apocalyptic number.

1320428723 is a deficient number, since it is larger than the sum of its proper divisors (1597477).

1320428723 is an equidigital number, since it uses as much as digits as its factorization.

1320428723 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1597476.

The product of its (nonzero) digits is 16128, while the sum is 32.

The square root of 1320428723 is about 36337.7038762770. The cubic root of 1320428723 is about 1097.0800583748.

Adding to 1320428723 its reverse (3278240231), we get a palindrome (4598668954).

The spelling of 1320428723 in words is "one billion, three hundred twenty million, four hundred twenty-eight thousand, seven hundred twenty-three".