728446431 has 4 divisors (see below), whose sum is σ = 971261912. Its totient is φ = 485630952.

The previous prime is 728446423. The next prime is 728446471. The reversal of 728446431 is 134644827.

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

It is not a de Polignac number, because 728446431 - 2³ = 728446423 is a prime.

It is a super-2 number, since 2×728446431² = 1061268405673275522, which contains 22 as substring.

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 728446431.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (728446471) 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, 121407736 + ... + 121407741.

It is an arithmetic number, because the mean of its divisors is an integer number (242815478).

Almost surely, 2^728446431 is an apocalyptic number.

728446431 is a deficient number, since it is larger than the sum of its proper divisors (242815481).

728446431 is a wasteful number, since it uses less digits than its factorization.

728446431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 242815480.

The product of its digits is 129024, while the sum is 39.

The square root of 728446431 is about 26989.7467753960. The cubic root of 728446431 is about 899.7721361410.

The spelling of 728446431 in words is "seven hundred twenty-eight million, four hundred forty-six thousand, four hundred thirty-one".