645890088884 has 6 divisors (see below), whose sum is σ = 1130307655554. Its totient is φ = 322945044440.

The previous prime is 645890088821. The next prime is 645890088889. The reversal of 645890088884 is 488880098546.

It can be written as a sum of positive squares in only one way, i.e., 363958824100 + 281931264784 = 603290^2 + 530972^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645890088889) 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, 80736261107 + ... + 80736261114.

It is an arithmetic number, because the mean of its divisors is an integer number (188384609259).

Almost surely, 2^645890088884 is an apocalyptic number.

It is an amenable number.

645890088884 is a deficient number, since it is larger than the sum of its proper divisors (484417566670).

645890088884 is a wasteful number, since it uses less digits than its factorization.

645890088884 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 161472522225 (or 161472522223 counting only the distinct ones).

The product of its (nonzero) digits is 141557760, while the sum is 68.

The spelling of 645890088884 in words is "six hundred forty-five billion, eight hundred ninety million, eighty-eight thousand, eight hundred eighty-four".