724821121 has 2 divisors, whose sum is σ = 724821122. Its totient is φ = 724821120.

The previous prime is 724821067. The next prime is 724821127. The reversal of 724821121 is 121128427.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 698862096 + 25959025 = 26436^2 + 5095^2 .

It is a cyclic number.

It is not a de Polignac number, because 724821121 - 2¹³ = 724812929 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 724821121.

It is not a weakly prime, because it can be changed into another prime (724821127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 362410560 + 362410561.

It is an arithmetic number, because the mean of its divisors is an integer number (362410561).

Almost surely, 2^724821121 is an apocalyptic number.

It is an amenable number.

724821121 is a deficient number, since it is larger than the sum of its proper divisors (1).

724821121 is an equidigital number, since it uses as much as digits as its factorization.

724821121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1792, while the sum is 28.

The square root of 724821121 is about 26922.5021311170. The cubic root of 724821121 is about 898.2770002259.

Adding to 724821121 its reverse (121128427), we get a palindrome (845949548).

The spelling of 724821121 in words is "seven hundred twenty-four million, eight hundred twenty-one thousand, one hundred twenty-one".