645144642319 has 2 divisors, whose sum is σ = 645144642320. Its totient is φ = 645144642318.

The previous prime is 645144642293. The next prime is 645144642349. The reversal of 645144642319 is 913246441546.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 645144642319 - 2⁹ = 645144641807 is a prime.

It is a super-2 number, since 2×645144642319² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (645144642349) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322572321159 + 322572321160.

It is an arithmetic number, because the mean of its divisors is an integer number (322572321160).

Almost surely, 2^645144642319 is an apocalyptic number.

645144642319 is a deficient number, since it is larger than the sum of its proper divisors (1).

645144642319 is an equidigital number, since it uses as much as digits as its factorization.

645144642319 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2488320, while the sum is 49.

The spelling of 645144642319 in words is "six hundred forty-five billion, one hundred forty-four million, six hundred forty-two thousand, three hundred nineteen".