645643604346 has 64 divisors (see below), whose sum is σ = 1465083002880. Its totient is φ = 188039793600.

The previous prime is 645643604341. The next prime is 645643604393. The reversal of 645643604346 is 643406346546.

It is not an unprimeable number, because it can be changed into a prime (645643604341) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1516531 + ... + 1895033.

It is an arithmetic number, because the mean of its divisors is an integer number (22891921920).

Almost surely, 2^645643604346 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 645643604346, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (732541501440).

645643604346 is an abundant number, since it is smaller than the sum of its proper divisors (819439398534).

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

645643604346 is a wasteful number, since it uses less digits than its factorization.

645643604346 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 379691.

The product of its (nonzero) digits is 14929920, while the sum is 51.

The spelling of 645643604346 in words is "six hundred forty-five billion, six hundred forty-three million, six hundred four thousand, three hundred forty-six".