645441011 has 2 divisors, whose sum is σ = 645441012. Its totient is φ = 645441010.

The previous prime is 645440977. The next prime is 645441037. The reversal of 645441011 is 110144546.

It is an a-pointer prime, because the next prime (645441037) can be obtained adding 645441011 to its sum of digits (26).

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 645441011 - 2⁶ = 645440947 is a prime.

It is not a weakly prime, because it can be changed into another prime (645449011) 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, 322720505 + 322720506.

It is an arithmetic number, because the mean of its divisors is an integer number (322720506).

Almost surely, 2^645441011 is an apocalyptic number.

645441011 is a deficient number, since it is larger than the sum of its proper divisors (1).

645441011 is an equidigital number, since it uses as much as digits as its factorization.

645441011 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1920, while the sum is 26.

The square root of 645441011 is about 25405.5311103704. The cubic root of 645441011 is about 864.2091342415.

Adding to 645441011 its reverse (110144546), we get a palindrome (755585557).

The spelling of 645441011 in words is "six hundred forty-five million, four hundred forty-one thousand, eleven".