645875559 has 32 divisors (see below), whose sum is σ = 1131264000. Its totient is φ = 356342112.

The previous prime is 645875533. The next prime is 645875563. The reversal of 645875559 is 955578546.

645875559 is a `hidden beast` number, since 6 + 4 + 5 + 87 + 5 + 559 = 666.

It is not a de Polignac number, because 645875559 - 2¹³ = 645867367 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645875519) 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 31 ways as a sum of consecutive naturals, for example, 53439 + ... + 64400.

It is an arithmetic number, because the mean of its divisors is an integer number (35352000).

Almost surely, 2^645875559 is an apocalyptic number.

645875559 is a deficient number, since it is larger than the sum of its proper divisors (485388441).

645875559 is a wasteful number, since it uses less digits than its factorization.

645875559 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 117884 (or 117878 counting only the distinct ones).

The product of its digits is 7560000, while the sum is 54.

The square root of 645875559 is about 25414.0819035432. The cubic root of 645875559 is about 864.4030358258.

The spelling of 645875559 in words is "six hundred forty-five million, eight hundred seventy-five thousand, five hundred fifty-nine".