645820078 has 8 divisors (see below), whose sum is σ = 970327872. Its totient is φ = 322377456.

The previous prime is 645820067. The next prime is 645820079. The reversal of 645820078 is 870028546.

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

It is a self number, because there is not a number n which added to its sum of digits gives 645820078.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645820079) 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 3 ways as a sum of consecutive naturals, for example, 264775 + ... + 267202.

It is an arithmetic number, because the mean of its divisors is an integer number (121290984).

Almost surely, 2^645820078 is an apocalyptic number.

645820078 is a deficient number, since it is larger than the sum of its proper divisors (324507794).

645820078 is a wasteful number, since it uses less digits than its factorization.

645820078 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 532586.

The product of its (nonzero) digits is 107520, while the sum is 40.

The square root of 645820078 is about 25412.9903395881. The cubic root of 645820078 is about 864.3782842477.

The spelling of 645820078 in words is "six hundred forty-five million, eight hundred twenty thousand, seventy-eight".