728284621 has 2 divisors, whose sum is σ = 728284622. Its totient is φ = 728284620.

The previous prime is 728284603. The next prime is 728284631. The reversal of 728284621 is 126482827.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 478296900 + 249987721 = 21870^2 + 15811^2 .

It is a cyclic number.

It is not a de Polignac number, because 728284621 - 2⁵ = 728284589 is a prime.

It is a super-2 number, since 2×728284621² = 1060796978370227282, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (728284631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 364142310 + 364142311.

It is an arithmetic number, because the mean of its divisors is an integer number (364142311).

Almost surely, 2^728284621 is an apocalyptic number.

It is an amenable number.

728284621 is a deficient number, since it is larger than the sum of its proper divisors (1).

728284621 is an equidigital number, since it uses as much as digits as its factorization.

728284621 is an evil number, because the sum of its binary digits is even.

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

The square root of 728284621 is about 26986.7489890872. The cubic root of 728284621 is about 899.7055089992.

The spelling of 728284621 in words is "seven hundred twenty-eight million, two hundred eighty-four thousand, six hundred twenty-one".