645128479 has 8 divisors (see below), whose sum is σ = 660859920. Its totient is φ = 629557056.

The previous prime is 645128467. The next prime is 645128503. The reversal of 645128479 is 974821546.

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

It is a cyclic number.

It is not a de Polignac number, because 645128479 - 2⁵ = 645128447 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645128179) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31824 + ... + 47989.

It is an arithmetic number, because the mean of its divisors is an integer number (82607490).

Almost surely, 2^645128479 is an apocalyptic number.

645128479 is a deficient number, since it is larger than the sum of its proper divisors (15731441).

645128479 is a wasteful number, since it uses less digits than its factorization.

645128479 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80009.

The product of its digits is 483840, while the sum is 46.

The square root of 645128479 is about 25399.3795002949. The cubic root of 645128479 is about 864.0696241440.

The spelling of 645128479 in words is "six hundred forty-five million, one hundred twenty-eight thousand, four hundred seventy-nine".