645939939546 has 48 divisors (see below), whose sum is σ = 1541883683808. Its totient is φ = 193801356000.

The previous prime is 645939939539. The next prime is 645939939559.

It is a happy number.

645939939546 is a `hidden beast` number, since 6 + 45 + 9 + 3 + 9 + 9 + 39 + 546 = 666.

645939939546 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×645939939546² (a number of 24 digits) contains 22 as substring.

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 23 ways as a sum of consecutive naturals, for example, 16130116 + ... + 16170111.

It is an arithmetic number, because the mean of its divisors is an integer number (32122576746).

Almost surely, 2^645939939546 is an apocalyptic number.

645939939546 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

645939939546 is an abundant number, since it is smaller than the sum of its proper divisors (895943744262).

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

645939939546 is a wasteful number, since it uses less digits than its factorization.

645939939546 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32300347 (or 32300344 counting only the distinct ones).

The product of its digits is 850305600, while the sum is 72.

The spelling of 645939939546 in words is "six hundred forty-five billion, nine hundred thirty-nine million, nine hundred thirty-nine thousand, five hundred forty-six".