645356064 has 72 divisors (see below), whose sum is σ = 1713594960. Its totient is φ = 212665600.

The previous prime is 645356051. The next prime is 645356077. The reversal of 645356064 is 460653546.

It is an interprime number because it is at equal distance from previous prime (645356051) and next prime (645356077).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 978967 + ... + 979625.

It is an arithmetic number, because the mean of its divisors is an integer number (23799930).

Almost surely, 2^645356064 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 645356064, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (856797480).

645356064 is an abundant number, since it is smaller than the sum of its proper divisors (1068238896).

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

645356064 is a wasteful number, since it uses less digits than its factorization.

645356064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 874 (or 765 counting only the distinct ones).

The product of its (nonzero) digits is 259200, while the sum is 39.

The square root of 645356064 is about 25403.8592343762. The cubic root of 645356064 is about 864.1712194964.

The spelling of 645356064 in words is "six hundred forty-five million, three hundred fifty-six thousand, sixty-four".