645880659 has 8 divisors (see below), whose sum is σ = 862097040. Its totient is φ = 430125696.

The previous prime is 645880657. The next prime is 645880673. The reversal of 645880659 is 956088546.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 645880659 - 2¹ = 645880657 is a prime.

It is not an unprimeable number, because it can be changed into a prime (645880657) 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 7 ways as a sum of consecutive naturals, for example, 112074 + ... + 117695.

It is an arithmetic number, because the mean of its divisors is an integer number (107762130).

Almost surely, 2^645880659 is an apocalyptic number.

645880659 is a deficient number, since it is larger than the sum of its proper divisors (216216381).

645880659 is a wasteful number, since it uses less digits than its factorization.

645880659 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 230709.

The product of its (nonzero) digits is 2073600, while the sum is 51.

The square root of 645880659 is about 25414.1822414179. The cubic root of 645880659 is about 864.4053110030.

The spelling of 645880659 in words is "six hundred forty-five million, eight hundred eighty thousand, six hundred fifty-nine".