645450001 has 24 divisors (see below), whose sum is σ = 762211296. Its totient is φ = 544924800.

The previous prime is 645449957. The next prime is 645450019. The reversal of 645450001 is 100054546.

It is not a de Polignac number, because 645450001 - 2¹⁹ = 644925713 is a prime.

It is a super-4 number, since 4×645450001⁴ (a number of 36 digits) contains 4444 as substring.

It is not an unprimeable number, because it can be changed into a prime (645450601) 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 23 ways as a sum of consecutive naturals, for example, 1609401 + ... + 1609801.

It is an arithmetic number, because the mean of its divisors is an integer number (31758804).

Almost surely, 2^645450001 is an apocalyptic number.

It is an amenable number.

645450001 is a deficient number, since it is larger than the sum of its proper divisors (116761295).

645450001 is a wasteful number, since it uses less digits than its factorization.

645450001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 829 (or 822 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 25.

The square root of 645450001 is about 25405.7080397300. The cubic root of 645450001 is about 864.2131465906.

The spelling of 645450001 in words is "six hundred forty-five million, four hundred fifty thousand, one".