103210721 has 2 divisors, whose sum is σ = 103210722. Its totient is φ = 103210720.

The previous prime is 103210711. The next prime is 103210759. The reversal of 103210721 is 127012301.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 77088400 + 26122321 = 8780^2 + 5111^2 .

It is a cyclic number.

It is not a de Polignac number, because 103210721 - 2¹⁴ = 103194337 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a self number, because there is not a number n which added to its sum of digits gives 103210721.

It is not a weakly prime, because it can be changed into another prime (103210711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 51605360 + 51605361.

It is an arithmetic number, because the mean of its divisors is an integer number (51605361).

Almost surely, 2^103210721 is an apocalyptic number.

It is an amenable number.

103210721 is a deficient number, since it is larger than the sum of its proper divisors (1).

103210721 is an equidigital number, since it uses as much as digits as its factorization.

103210721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 84, while the sum is 17.

The square root of 103210721 is about 10159.2677393600. The cubic root of 103210721 is about 469.0742620134.

The spelling of 103210721 in words is "one hundred three million, two hundred ten thousand, seven hundred twenty-one".