645065055631 has 2 divisors, whose sum is σ = 645065055632. Its totient is φ = 645065055630.

The previous prime is 645065055589. The next prime is 645065055667. The reversal of 645065055631 is 136550560546.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 645065055631 - 2¹⁹ = 645064531343 is a prime.

It is a super-2 number, since 2×645065055631² (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 (645065055331) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322532527815 + 322532527816.

It is an arithmetic number, because the mean of its divisors is an integer number (322532527816).

Almost surely, 2^645065055631 is an apocalyptic number.

645065055631 is a deficient number, since it is larger than the sum of its proper divisors (1).

645065055631 is an equidigital number, since it uses as much as digits as its factorization.

645065055631 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1620000, while the sum is 46.

The spelling of 645065055631 in words is "six hundred forty-five billion, sixty-five million, fifty-five thousand, six hundred thirty-one".