645563374 has 12 divisors (see below), whose sum is σ = 1002890304. Its totient is φ = 311650472.

The previous prime is 645563353. The next prime is 645563381. The reversal of 645563374 is 473365546.

It is a self number, because there is not a number n which added to its sum of digits gives 645563374.

It is a congruent number.

It is an unprimeable number.

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 in 5 ways as a sum of consecutive naturals, for example, 190222 + ... + 193585.

It is an arithmetic number, because the mean of its divisors is an integer number (83574192).

Almost surely, 2^645563374 is an apocalyptic number.

645563374 is a deficient number, since it is larger than the sum of its proper divisors (357326930).

645563374 is a wasteful number, since it uses less digits than its factorization.

645563374 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 383867 (or 383838 counting only the distinct ones).

The product of its digits is 907200, while the sum is 43.

The square root of 645563374 is about 25407.9391923076. The cubic root of 645563374 is about 864.2637431774.

The spelling of 645563374 in words is "six hundred forty-five million, five hundred sixty-three thousand, three hundred seventy-four".