721478033 has 2 divisors, whose sum is σ = 721478034. Its totient is φ = 721478032.

The previous prime is 721478003. The next prime is 721478039. The reversal of 721478033 is 330874127.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 681888769 + 39589264 = 26113^2 + 6292^2 .

It is an emirp because it is prime and its reverse (330874127) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 721478033 - 2¹⁴ = 721461649 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 721477984 and 721478002.

It is not a weakly prime, because it can be changed into another prime (721478039) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360739016 + 360739017.

It is an arithmetic number, because the mean of its divisors is an integer number (360739017).

Almost surely, 2^721478033 is an apocalyptic number.

It is an amenable number.

721478033 is a deficient number, since it is larger than the sum of its proper divisors (1).

721478033 is an equidigital number, since it uses as much as digits as its factorization.

721478033 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 28224, while the sum is 35.

The square root of 721478033 is about 26860.3431288582. The cubic root of 721478033 is about 896.8938323539.

The spelling of 721478033 in words is "seven hundred twenty-one million, four hundred seventy-eight thousand, thirty-three".