645543629 has 2 divisors, whose sum is σ = 645543630. Its totient is φ = 645543628.

The previous prime is 645543617. The next prime is 645543641. The reversal of 645543629 is 926345546.

It is a balanced prime because it is at equal distance from previous prime (645543617) and next prime (645543641).

It can be written as a sum of positive squares in only one way, i.e., 625500100 + 20043529 = 25010^2 + 4477^2 .

It is a cyclic number.

It is not a de Polignac number, because 645543629 - 2¹² = 645539533 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 645543629.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (645543029) 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, 322771814 + 322771815.

It is an arithmetic number, because the mean of its divisors is an integer number (322771815).

Almost surely, 2^645543629 is an apocalyptic number.

It is an amenable number.

645543629 is a deficient number, since it is larger than the sum of its proper divisors (1).

645543629 is an equidigital number, since it uses as much as digits as its factorization.

645543629 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 777600, while the sum is 44.

The square root of 645543629 is about 25407.5506296849. The cubic root of 645543629 is about 864.2549317205.

The spelling of 645543629 in words is "six hundred forty-five million, five hundred forty-three thousand, six hundred twenty-nine".