645361582336 has 243 divisors, whose sum is σ = 1407881349021. Its totient is φ = 295219279872.

The previous prime is 645361582291. The next prime is 645361582351. The reversal of 645361582336 is 633285163546.

The square root of 645361582336 is 803344.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 577478406400 + 67883175936 = 759920^2 + 260544^2 .

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 10938331875 + ... + 10938331933.

Almost surely, 2^645361582336 is an apocalyptic number.

645361582336 is the 803344-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 645361582336

645361582336 is an abundant number, since it is smaller than the sum of its proper divisors (762519766685).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

645361582336 is an frugal number, since it uses more digits than its factorization.

645361582336 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 254 (or 121 counting only the distinct ones).

The product of its digits is 9331200, while the sum is 52.

The spelling of 645361582336 in words is "six hundred forty-five billion, three hundred sixty-one million, five hundred eighty-two thousand, three hundred thirty-six".