645633336546 has 64 divisors (see below), whose sum is σ = 1566229271040. Its totient is φ = 195514272720.

The previous prime is 645633336539. The next prime is 645633336577.

It is a happy number.

645633336546 is a `hidden beast` number, since 6 + 4 + 5 + 63 + 3 + 3 + 36 + 546 = 666.

645633336546 is nontrivially palindromic in base 10.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a junction number, because it is equal to n+sod(n) for n = 645633336492 and 645633336501.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 514441 + ... + 1247363.

It is an arithmetic number, because the mean of its divisors is an integer number (24472332360).

Almost surely, 2^645633336546 is an apocalyptic number.

645633336546 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

645633336546 is an abundant number, since it is smaller than the sum of its proper divisors (920595934494).

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

645633336546 is a wasteful number, since it uses less digits than its factorization.

645633336546 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 734428 (or 734422 counting only the distinct ones).

The product of its digits is 41990400, while the sum is 54.

The spelling of 645633336546 in words is "six hundred forty-five billion, six hundred thirty-three million, three hundred thirty-six thousand, five hundred forty-six".