645367818 has 16 divisors (see below), whose sum is σ = 1300158720. Its totient is φ = 213552096.

The previous prime is 645367781. The next prime is 645367847. The reversal of 645367818 is 818763546.

It is a super-2 number, since 2×645367818² = 832999241020162248, which contains 22 as substring.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 391738 + ... + 393381.

It is an arithmetic number, because the mean of its divisors is an integer number (81259920).

Almost surely, 2^645367818 is an apocalyptic number.

645367818 is an abundant number, since it is smaller than the sum of its proper divisors (654790902).

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

645367818 is a wasteful number, since it uses less digits than its factorization.

645367818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 785261.

The product of its digits is 967680, while the sum is 48.

The square root of 645367818 is about 25404.0905761257. The cubic root of 645367818 is about 864.1764659061.

The spelling of 645367818 in words is "six hundred forty-five million, three hundred sixty-seven thousand, eight hundred eighteen".