10000721 has 2 divisors, whose sum is σ = 10000722. Its totient is φ = 10000720.

The previous prime is 10000691. The next prime is 10000723. The reversal of 10000721 is 12700001.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8620096 + 1380625 = 2936^2 + 1175^2 .

It is an emirp because it is prime and its reverse (12700001) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 10000721 - 2⁶ = 10000657 is a prime.

Together with 10000723, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (10000723) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5000360 + 5000361.

It is an arithmetic number, because the mean of its divisors is an integer number (5000361).

Almost surely, 2^10000721 is an apocalyptic number.

It is an amenable number.

10000721 is a deficient number, since it is larger than the sum of its proper divisors (1).

10000721 is an equidigital number, since it uses as much as digits as its factorization.

10000721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 14, while the sum is 11.

The square root of 10000721 is about 3162.3916582233. The cubic root of 10000721 is about 215.4486467035.

Adding to 10000721 its reverse (12700001), we get a palindrome (22700722).

The spelling of 10000721 in words is "ten million, seven hundred twenty-one", and thus it is an aban number.