645123654594 has 24 divisors (see below), whose sum is σ = 1402233642732. Its totient is φ = 214354183680.

The previous prime is 645123654589. The next prime is 645123654599. The reversal of 645123654594 is 495456321546.

645123654594 is a `hidden beast` number, since 6 + 4 + 5 + 1 + 2 + 3 + 6 + 545 + 94 = 666.

It is an interprime number because it is at equal distance from previous prime (645123654589) and next prime (645123654599).

It can be written as a sum of positive squares in 2 ways, for example, as 470054216025 + 175069438569 = 685605^2 + 418413^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 645123654594.

It is not an unprimeable number, because it can be changed into a prime (645123654599) 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 in 11 ways as a sum of consecutive naturals, for example, 57247087 + ... + 57258354.

Almost surely, 2^645123654594 is an apocalyptic number.

645123654594 is an abundant number, since it is smaller than the sum of its proper divisors (757109988138).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

645123654594 is a wasteful number, since it uses less digits than its factorization.

645123654594 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114505762 (or 114505759 counting only the distinct ones).

The product of its digits is 15552000, while the sum is 54.

The spelling of 645123654594 in words is "six hundred forty-five billion, one hundred twenty-three million, six hundred fifty-four thousand, five hundred ninety-four".