645226560 has 560 divisors, whose sum is σ = 2620012032. Its totient is φ = 149299200.

The previous prime is 645226531. The next prime is 645226577. The reversal of 645226560 is 65622546.

645226560 is a `hidden beast` number, since 645 + 2 + 2 + 6 + 5 + 6 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 8838684 + ... + 8838756.

Almost surely, 2^645226560 is an apocalyptic number.

645226560 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 645226560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1310006016).

645226560 is an abundant number, since it is smaller than the sum of its proper divisors (1974785472).

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

645226560 is a wasteful number, since it uses less digits than its factorization.

645226560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 144 (or 125 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 36.

The square root of 645226560 is about 25401.3102024285. The cubic root of 645226560 is about 864.1134110386.

The spelling of 645226560 in words is "six hundred forty-five million, two hundred twenty-six thousand, five hundred sixty".