645505546 has 8 divisors (see below), whose sum is σ = 1106580960. Its totient is φ = 276645228.

The previous prime is 645505463. The next prime is 645505547.

645505546 is nontrivially palindromic in base 10.

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

It is a junction number, because it is equal to n+sod(n) for n = 645505499 and 645505508.

It is not an unprimeable number, because it can be changed into a prime (645505547) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23053756 + ... + 23053783.

It is an arithmetic number, because the mean of its divisors is an integer number (138322620).

Almost surely, 2^645505546 is an apocalyptic number.

645505546 is a deficient number, since it is larger than the sum of its proper divisors (461075414).

645505546 is a wasteful number, since it uses less digits than its factorization.

645505546 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46107548.

The product of its (nonzero) digits is 360000, while the sum is 40.

The square root of 645505546 is about 25406.8011760631. The cubic root of 645505546 is about 864.2379361908.

The spelling of 645505546 in words is "six hundred forty-five million, five hundred five thousand, five hundred forty-six".