645606620344 has 16 divisors (see below), whose sum is σ = 1383442758000. Its totient is φ = 276688551552.

The previous prime is 645606620273. The next prime is 645606620389. The reversal of 645606620344 is 443026606546.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 645606620294 and 645606620303.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5764344769 + ... + 5764344880.

It is an arithmetic number, because the mean of its divisors is an integer number (86465172375).

Almost surely, 2^645606620344 is an apocalyptic number.

It is an amenable number.

645606620344 is an abundant number, since it is smaller than the sum of its proper divisors (737836137656).

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

645606620344 is a wasteful number, since it uses less digits than its factorization.

645606620344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11528689662 (or 11528689658 counting only the distinct ones).

The product of its (nonzero) digits is 2488320, while the sum is 46.

The spelling of 645606620344 in words is "six hundred forty-five billion, six hundred six million, six hundred twenty thousand, three hundred forty-four".