653364721 has 3 divisors (see below), whose sum is σ = 653390283. Its totient is φ = 653339160.

The previous prime is 653364707. The next prime is 653364731. The reversal of 653364721 is 127463356.

The square root of 653364721 is 25561.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 534118321 + 119246400 = 23111^2 + 10920^2 .

It is not a de Polignac number, because 653364721 - 2¹¹ = 653362673 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (653364731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 12781 + ... + 38341.

It is an arithmetic number, because the mean of its divisors is an integer number (217796761).

Almost surely, 2^653364721 is an apocalyptic number.

653364721 is the 25561-st square number.

653364721 is the 12781-st centered octagonal number.

It is an amenable number.

653364721 is a deficient number, since it is larger than the sum of its proper divisors (25562).

653364721 is an frugal number, since it uses more digits than its factorization.

653364721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51122 (or 25561 counting only the distinct ones).

The product of its digits is 90720, while the sum is 37.

The cubic root of 653364721 is about 867.7312274407.

The spelling of 653364721 in words is "six hundred fifty-three million, three hundred sixty-four thousand, seven hundred twenty-one".