721560001 has 2 divisors, whose sum is σ = 721560002. Its totient is φ = 721560000.

The previous prime is 721559989. The next prime is 721560013. The reversal of 721560001 is 100065127.

It is a balanced prime because it is at equal distance from previous prime (721559989) and next prime (721560013).

It can be written as a sum of positive squares in only one way, i.e., 654336400 + 67223601 = 25580^2 + 8199^2 .

It is a cyclic number.

It is not a de Polignac number, because 721560001 - 2⁷ = 721559873 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (721560401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360780000 + 360780001.

It is an arithmetic number, because the mean of its divisors is an integer number (360780001).

Almost surely, 2^721560001 is an apocalyptic number.

It is an amenable number.

721560001 is a deficient number, since it is larger than the sum of its proper divisors (1).

721560001 is an equidigital number, since it uses as much as digits as its factorization.

721560001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 420, while the sum is 22.

The square root of 721560001 is about 26861.8689037081. The cubic root of 721560001 is about 896.9277968021.

The spelling of 721560001 in words is "seven hundred twenty-one million, five hundred sixty thousand, one".