645802853 has 4 divisors (see below), whose sum is σ = 660821568. Its totient is φ = 630784140.

The previous prime is 645802771. The next prime is 645802877. The reversal of 645802853 is 358208546.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 645802853 - 2¹⁰ = 645801829 is a prime.

It is a super-2 number, since 2×645802853² = 834122649885879218, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 645802853.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645802753) 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, 7509293 + ... + 7509378.

It is an arithmetic number, because the mean of its divisors is an integer number (165205392).

Almost surely, 2^645802853 is an apocalyptic number.

It is an amenable number.

645802853 is a deficient number, since it is larger than the sum of its proper divisors (15018715).

645802853 is a wasteful number, since it uses less digits than its factorization.

645802853 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15018714.

The product of its (nonzero) digits is 230400, while the sum is 41.

The square root of 645802853 is about 25412.6514358498. The cubic root of 645802853 is about 864.3705994199.

The spelling of 645802853 in words is "six hundred forty-five million, eight hundred two thousand, eight hundred fifty-three".