724717621 has 2 divisors, whose sum is σ = 724717622. Its totient is φ = 724717620.

The previous prime is 724717619. The next prime is 724717663. The reversal of 724717621 is 126717427.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 677300625 + 47416996 = 26025^2 + 6886^2 .

It is a cyclic number.

It is not a de Polignac number, because 724717621 - 2¹ = 724717619 is a prime.

Together with 724717619, it forms a pair of twin primes.

It is equal to p_37465660 and since 724717621 and 37465660 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (724717921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 362358810 + 362358811.

It is an arithmetic number, because the mean of its divisors is an integer number (362358811).

Almost surely, 2^724717621 is an apocalyptic number.

It is an amenable number.

724717621 is a deficient number, since it is larger than the sum of its proper divisors (1).

724717621 is an equidigital number, since it uses as much as digits as its factorization.

724717621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32928, while the sum is 37.

The square root of 724717621 is about 26920.5798785985. The cubic root of 724717621 is about 898.2342420462.

The spelling of 724717621 in words is "seven hundred twenty-four million, seven hundred seventeen thousand, six hundred twenty-one".