645489471 has 32 divisors (see below), whose sum is σ = 982941696. Its totient is φ = 373212000.

The previous prime is 645489461. The next prime is 645489497. The reversal of 645489471 is 174984546.

It is not a de Polignac number, because 645489471 - 2⁷ = 645489343 is a prime.

It is a super-3 number, since 3×645489471³ (a number of 27 digits) contains 333 as substring.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 645489471.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645489401) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 68190 + ... + 77076.

It is an arithmetic number, because the mean of its divisors is an integer number (30716928).

Almost surely, 2^645489471 is an apocalyptic number.

645489471 is a deficient number, since it is larger than the sum of its proper divisors (337452225).

645489471 is a wasteful number, since it uses less digits than its factorization.

645489471 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9003.

The product of its digits is 967680, while the sum is 48.

The square root of 645489471 is about 25406.4848217930. The cubic root of 645489471 is about 864.2307621031.

The spelling of 645489471 in words is "six hundred forty-five million, four hundred eighty-nine thousand, four hundred seventy-one".