645728001 has 8 divisors (see below), whose sum is σ = 865781280. Its totient is φ = 428080032.

The previous prime is 645727993. The next prime is 645728009. The reversal of 645728001 is 100827546.

It is an interprime number because it is at equal distance from previous prime (645727993) and next prime (645728009).

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

It is not a de Polignac number, because 645728001 - 2³ = 645727993 is a prime.

It is not an unprimeable number, because it can be changed into a prime (645728009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 600700 + ... + 601773.

It is an arithmetic number, because the mean of its divisors is an integer number (108222660).

Almost surely, 2^645728001 is an apocalyptic number.

It is an amenable number.

645728001 is a deficient number, since it is larger than the sum of its proper divisors (220053279).

645728001 is a wasteful number, since it uses less digits than its factorization.

645728001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1202655.

The product of its (nonzero) digits is 13440, while the sum is 33.

The square root of 645728001 is about 25411.1786621558. The cubic root of 645728001 is about 864.3372030732.

The spelling of 645728001 in words is "six hundred forty-five million, seven hundred twenty-eight thousand, one".