645206631307 has 24 divisors (see below), whose sum is σ = 789846625536. Its totient is φ = 516107245104.

The previous prime is 645206631259. The next prime is 645206631317. The reversal of 645206631307 is 703136602546.

It is not a de Polignac number, because 645206631307 - 2¹⁵ = 645206598539 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (645206631317) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1736103 + ... + 2074720.

It is an arithmetic number, because the mean of its divisors is an integer number (32910276064).

Almost surely, 2^645206631307 is an apocalyptic number.

645206631307 is a gapful number since it is divisible by the number (67) formed by its first and last digit.

645206631307 is a deficient number, since it is larger than the sum of its proper divisors (144639994229).

645206631307 is a wasteful number, since it uses less digits than its factorization.

645206631307 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3810935 (or 3810916 counting only the distinct ones).

The product of its (nonzero) digits is 544320, while the sum is 43.

The spelling of 645206631307 in words is "six hundred forty-five billion, two hundred six million, six hundred thirty-one thousand, three hundred seven".