721003001 has 2 divisors, whose sum is σ = 721003002. Its totient is φ = 721003000.

The previous prime is 721002949. The next prime is 721003061. The reversal of 721003001 is 100300127.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 488410000 + 232593001 = 22100^2 + 15251^2 .

It is an emirp because it is prime and its reverse (100300127) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-721003001 is a prime.

It is not a weakly prime, because it can be changed into another prime (721003061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360501500 + 360501501.

It is an arithmetic number, because the mean of its divisors is an integer number (360501501).

Almost surely, 2^721003001 is an apocalyptic number.

It is an amenable number.

721003001 is a deficient number, since it is larger than the sum of its proper divisors (1).

721003001 is an equidigital number, since it uses as much as digits as its factorization.

721003001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 42, while the sum is 14.

The square root of 721003001 is about 26851.4990456771. The cubic root of 721003001 is about 896.6969463355.

Adding to 721003001 its reverse (100300127), we get a palindrome (821303128).

The spelling of 721003001 in words is "seven hundred twenty-one million, three thousand, one".