645798479 has 4 divisors (see below), whose sum is σ = 666630720. Its totient is φ = 624966240.

The previous prime is 645798473. The next prime is 645798493. The reversal of 645798479 is 974897546.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 645798479 - 2¹⁶ = 645732943 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 (645798473) 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 3 ways as a sum of consecutive naturals, for example, 10416074 + ... + 10416135.

It is an arithmetic number, because the mean of its divisors is an integer number (166657680).

Almost surely, 2^645798479 is an apocalyptic number.

645798479 is a deficient number, since it is larger than the sum of its proper divisors (20832241).

645798479 is a wasteful number, since it uses less digits than its factorization.

645798479 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20832240.

The product of its digits is 15240960, while the sum is 59.

The square root of 645798479 is about 25412.5653762071. The cubic root of 645798479 is about 864.3686479649.

The spelling of 645798479 in words is "six hundred forty-five million, seven hundred ninety-eight thousand, four hundred seventy-nine".