645907201 has 2 divisors, whose sum is σ = 645907202. Its totient is φ = 645907200.

The previous prime is 645907177. The next prime is 645907243. The reversal of 645907201 is 102709546.

645907201 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 491774976 + 154132225 = 22176^2 + 12415^2 .

It is a cyclic number.

It is not a de Polignac number, because 645907201 - 2²³ = 637518593 is a prime.

It is a super-2 number, since 2×645907201² = 834392224607308802, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (645907901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322953600 + 322953601.

It is an arithmetic number, because the mean of its divisors is an integer number (322953601).

Almost surely, 2^645907201 is an apocalyptic number.

It is an amenable number.

645907201 is a deficient number, since it is larger than the sum of its proper divisors (1).

645907201 is an equidigital number, since it uses as much as digits as its factorization.

645907201 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15120, while the sum is 34.

The square root of 645907201 is about 25414.7044248010. The cubic root of 645907201 is about 864.4171515451.

The spelling of 645907201 in words is "six hundred forty-five million, nine hundred seven thousand, two hundred one".