645479121974546 has 8 divisors (see below), whose sum is σ = 969260898985020. Its totient is φ = 322392155646208.

The previous prime is 645479121974537. The next prime is 645479121974549.

645479121974546 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in 2 ways, for example, as 614703311690521 + 30775810284025 = 24793211^2 + 5547595^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×645479121974546² (a number of 30 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (645479121974549) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 173702668211 + ... + 173702671926.

Almost surely, 2^{645479121974546} is an apocalyptic number.

645479121974546 is a deficient number, since it is larger than the sum of its proper divisors (323781777010474).

645479121974546 is a wasteful number, since it uses less digits than its factorization.

645479121974546 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 347405341068.

The product of its digits is 1828915200, while the sum is 74.

The spelling of 645479121974546 in words is "six hundred forty-five trillion, four hundred seventy-nine billion, one hundred twenty-one million, nine hundred seventy-four thousand, five hundred forty-six".