1720721227 has 2 divisors, whose sum is σ = 1720721228. Its totient is φ = 1720721226.

The previous prime is 1720721201. The next prime is 1720721231. The reversal of 1720721227 is 7221270271.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1720721227 - 2¹¹ = 1720719179 is a prime.

It is not a weakly prime, because it can be changed into another prime (1720721237) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 860360613 + 860360614.

It is an arithmetic number, because the mean of its divisors is an integer number (860360614).

Almost surely, 2^1720721227 is an apocalyptic number.

1720721227 is a deficient number, since it is larger than the sum of its proper divisors (1).

1720721227 is an equidigital number, since it uses as much as digits as its factorization.

1720721227 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5488, while the sum is 31.

The square root of 1720721227 is about 41481.5769589344. The cubic root of 1720721227 is about 1198.3127275476.

Adding to 1720721227 its reverse (7221270271), we get a palindrome (8941991498).

The spelling of 1720721227 in words is "one billion, seven hundred twenty million, seven hundred twenty-one thousand, two hundred twenty-seven".