645715207 has 2 divisors, whose sum is σ = 645715208. Its totient is φ = 645715206.

The previous prime is 645715201. The next prime is 645715211. The reversal of 645715207 is 702517546.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-645715207 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (645715201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322857603 + 322857604.

It is an arithmetic number, because the mean of its divisors is an integer number (322857604).

Almost surely, 2^645715207 is an apocalyptic number.

645715207 is a deficient number, since it is larger than the sum of its proper divisors (1).

645715207 is an equidigital number, since it uses as much as digits as its factorization.

645715207 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 58800, while the sum is 37.

The square root of 645715207 is about 25410.9269213069. The cubic root of 645715207 is about 864.3314945792.

The spelling of 645715207 in words is "six hundred forty-five million, seven hundred fifteen thousand, two hundred seven".