645765567546 has 32 divisors (see below), whose sum is σ = 1408980672000. Its totient is φ = 195681311280.

The previous prime is 645765567533. The next prime is 645765567583.

645765567546 is nontrivially palindromic in base 10.

It is a Harshad number since it is a multiple of its sum of digits (66).

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2883105 + ... + 3099003.

It is an arithmetic number, because the mean of its divisors is an integer number (44030646000).

Almost surely, 2^645765567546 is an apocalyptic number.

645765567546 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

645765567546 is an abundant number, since it is smaller than the sum of its proper divisors (763215104454).

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

645765567546 is a wasteful number, since it uses less digits than its factorization.

645765567546 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 261234.

The product of its digits is 635040000, while the sum is 66.

The spelling of 645765567546 in words is "six hundred forty-five billion, seven hundred sixty-five million, five hundred sixty-seven thousand, five hundred forty-six".