645791001 has 8 divisors (see below), whose sum is σ = 864098400. Its totient is φ = 429005472.

The previous prime is 645790997. The next prime is 645791017. The reversal of 645791001 is 100197546.

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

It is not a de Polignac number, because 645791001 - 2² = 645790997 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (645795001) 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, 379476 + ... + 381173.

It is an arithmetic number, because the mean of its divisors is an integer number (108012300).

Almost surely, 2^645791001 is an apocalyptic number.

It is an amenable number.

645791001 is a deficient number, since it is larger than the sum of its proper divisors (218307399).

645791001 is a wasteful number, since it uses less digits than its factorization.

645791001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 760935.

The product of its (nonzero) digits is 7560, while the sum is 33.

The square root of 645791001 is about 25412.4182438429. The cubic root of 645791001 is about 864.3653116436.

The spelling of 645791001 in words is "six hundred forty-five million, seven hundred ninety-one thousand, one".