645474929474546 has 16 divisors (see below), whose sum is σ = 969140139860760. Its totient is φ = 322428229914240.

The previous prime is 645474929474539. The next prime is 645474929474569.

645474929474546 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in 4 ways, for example, as 505164057981025 + 140310871493521 = 22475855^2 + 11845289^2 .

It is a super-2 number, since 2×645474929474546² (a number of 30 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (80) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 91263800 + ... + 98081756.

Almost surely, 2^{645474929474546} is an apocalyptic number.

645474929474546 is a deficient number, since it is larger than the sum of its proper divisors (323665210386214).

645474929474546 is a wasteful number, since it uses less digits than its factorization.

645474929474546 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6863309.

The product of its digits is 29262643200, while the sum is 80.

The spelling of 645474929474546 in words is "six hundred forty-five trillion, four hundred seventy-four billion, nine hundred twenty-nine million, four hundred seventy-four thousand, five hundred forty-six".