645772813056 has 432 divisors, whose sum is σ = 2204504527680. Its totient is φ = 177967595520.

The previous prime is 645772813051. The next prime is 645772813079. The reversal of 645772813056 is 650318277546.

645772813056 is a `hidden beast` number, since 6 + 4 + 57 + 7 + 281 + 305 + 6 = 666.

It is a hoax number, since the sum of its digits (54) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 645772812993 and 645772813011.

It is not an unprimeable number, because it can be changed into a prime (645772813051) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 58845586 + ... + 58856558.

It is an arithmetic number, because the mean of its divisors is an integer number (5103019740).

Almost surely, 2^645772813056 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 645772813056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1102252263840).

645772813056 is an abundant number, since it is smaller than the sum of its proper divisors (1558731714624).

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

645772813056 is a wasteful number, since it uses less digits than its factorization.

645772813056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11132 (or 11115 counting only the distinct ones).

The product of its (nonzero) digits is 8467200, while the sum is 54.

The spelling of 645772813056 in words is "six hundred forty-five billion, seven hundred seventy-two million, eight hundred thirteen thousand, fifty-six".