728422861 has 4 divisors (see below), whose sum is σ = 739294912. Its totient is φ = 717550812.

The previous prime is 728422859. The next prime is 728422879. The reversal of 728422861 is 168224827.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 728422861 - 2¹ = 728422859 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (728425861) 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, 5435925 + ... + 5436058.

It is an arithmetic number, because the mean of its divisors is an integer number (184823728).

Almost surely, 2^728422861 is an apocalyptic number.

It is an amenable number.

728422861 is a deficient number, since it is larger than the sum of its proper divisors (10872051).

728422861 is a wasteful number, since it uses less digits than its factorization.

728422861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10872050.

The product of its digits is 86016, while the sum is 40.

The square root of 728422861 is about 26989.3101245660. The cubic root of 728422861 is about 899.7624315344.

The spelling of 728422861 in words is "seven hundred twenty-eight million, four hundred twenty-two thousand, eight hundred sixty-one".