645884835 has 32 divisors (see below), whose sum is σ = 1055351808. Its totient is φ = 337236480.

The previous prime is 645884821. The next prime is 645884851. The reversal of 645884835 is 538488546.

It is a happy number.

It is not a de Polignac number, because 645884835 - 2⁴ = 645884819 is a prime.

It is a super-3 number, since 3×645884835³ (a number of 27 digits) contains 333 as substring.

It is an unprimeable number.

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, 138390 + ... + 142980.

It is an arithmetic number, because the mean of its divisors is an integer number (32979744).

Almost surely, 2^645884835 is an apocalyptic number.

645884835 is a deficient number, since it is larger than the sum of its proper divisors (409466973).

645884835 is a wasteful number, since it uses less digits than its factorization.

645884835 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4795.

The product of its digits is 3686400, while the sum is 51.

The square root of 645884835 is about 25414.2644001356. The cubic root of 645884835 is about 864.4071739626.

The spelling of 645884835 in words is "six hundred forty-five million, eight hundred eighty-four thousand, eight hundred thirty-five".