220720001 has 2 divisors, whose sum is σ = 220720002. Its totient is φ = 220720000.

The previous prime is 220719997. The next prime is 220720007. The reversal of 220720001 is 100027022.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 125462401 + 95257600 = 11201^2 + 9760^2 .

It is a cyclic number.

It is not a de Polignac number, because 220720001 - 2² = 220719997 is a prime.

It is not a weakly prime, because it can be changed into another prime (220720007) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110360000 + 110360001.

It is an arithmetic number, because the mean of its divisors is an integer number (110360001).

Almost surely, 2^220720001 is an apocalyptic number.

It is an amenable number.

220720001 is a deficient number, since it is larger than the sum of its proper divisors (1).

220720001 is an equidigital number, since it uses as much as digits as its factorization.

220720001 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 56, while the sum is 14.

The square root of 220720001 is about 14856.6483770735. The cubic root of 220720001 is about 604.3389186368.

Adding to 220720001 its reverse (100027022), we get a palindrome (320747023).

The spelling of 220720001 in words is "two hundred twenty million, seven hundred twenty thousand, one".