645902753 has 2 divisors, whose sum is σ = 645902754. Its totient is φ = 645902752.

The previous prime is 645902729. The next prime is 645902771. The reversal of 645902753 is 357209546.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 644804449 + 1098304 = 25393^2 + 1048^2 .

It is a cyclic number.

It is not a de Polignac number, because 645902753 - 2⁸ = 645902497 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 645902753.

It is not a weakly prime, because it can be changed into another prime (645907753) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322951376 + 322951377.

It is an arithmetic number, because the mean of its divisors is an integer number (322951377).

Almost surely, 2^645902753 is an apocalyptic number.

It is an amenable number.

645902753 is a deficient number, since it is larger than the sum of its proper divisors (1).

645902753 is an equidigital number, since it uses as much as digits as its factorization.

645902753 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 226800, while the sum is 41.

The square root of 645902753 is about 25414.6169162551. The cubic root of 645902753 is about 864.4151672888.

The spelling of 645902753 in words is "six hundred forty-five million, nine hundred two thousand, seven hundred fifty-three".