645092693568 has 1120 divisors, whose sum is σ = 2179566766080. Its totient is φ = 187878113280.

The previous prime is 645092693563. The next prime is 645092693569. The reversal of 645092693568 is 865396290546.

645092693568 is a `hidden beast` number, since 6 + 4 + 5 + 0 + 9 + 2 + 69 + 3 + 568 = 666.

It is a super-2 number, since 2×645092693568² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (645092693563) by changing a digit.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 7248232468 + ... + 7248232556.

Almost surely, 2^645092693568 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 645092693568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1089783383040).

645092693568 is an abundant number, since it is smaller than the sum of its proper divisors (1534474072512).

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

645092693568 is a wasteful number, since it uses less digits than its factorization.

645092693568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 257 (or 238 counting only the distinct ones).

The product of its (nonzero) digits is 83980800, while the sum is 63.

The spelling of 645092693568 in words is "six hundred forty-five billion, ninety-two million, six hundred ninety-three thousand, five hundred sixty-eight".