721741973 has 2 divisors, whose sum is σ = 721741974. Its totient is φ = 721741972.

The previous prime is 721741949. The next prime is 721741981. The reversal of 721741973 is 379147127.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 583608964 + 138133009 = 24158^2 + 11753^2 .

It is a cyclic number.

It is not a de Polignac number, because 721741973 - 2¹⁶ = 721676437 is a prime.

It is a super-2 number, since 2×721741973² = 1041822951179865458, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 721741973.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (721741073) 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, 360870986 + 360870987.

It is an arithmetic number, because the mean of its divisors is an integer number (360870987).

Almost surely, 2^721741973 is an apocalyptic number.

It is an amenable number.

721741973 is a deficient number, since it is larger than the sum of its proper divisors (1).

721741973 is an equidigital number, since it uses as much as digits as its factorization.

721741973 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 74088, while the sum is 41.

The square root of 721741973 is about 26865.2558707339. The cubic root of 721741973 is about 897.0031899439.

It can be divided in two parts, 72174 and 1973, that added together give a palindrome (74147).

The spelling of 721741973 in words is "seven hundred twenty-one million, seven hundred forty-one thousand, nine hundred seventy-three".