731284321 has 4 divisors (see below), whose sum is σ = 735511572. Its totient is φ = 727057072.

The previous prime is 731284319. The next prime is 731284349. The reversal of 731284321 is 123482137.

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

It can be written as a sum of positive squares in 2 ways, for example, as 285610000 + 445674321 = 16900^2 + 21111^2 .

It is a cyclic number.

It is not a de Polignac number, because 731284321 - 2¹ = 731284319 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (731284381) 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, 2113366 + ... + 2113711.

It is an arithmetic number, because the mean of its divisors is an integer number (183877893).

Almost surely, 2^731284321 is an apocalyptic number.

It is an amenable number.

731284321 is a deficient number, since it is larger than the sum of its proper divisors (4227251).

731284321 is a wasteful number, since it uses less digits than its factorization.

731284321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4227250.

The product of its digits is 8064, while the sum is 31.

The square root of 731284321 is about 27042.2691540484. The cubic root of 731284321 is about 900.9390696182.

The spelling of 731284321 in words is "seven hundred thirty-one million, two hundred eighty-four thousand, three hundred twenty-one".