645163110081 has 32 divisors (see below), whose sum is σ = 1121862362880. Its totient is φ = 358700721408.

The previous prime is 645163110061. The next prime is 645163110083. The reversal of 645163110081 is 180011361546.

It is a happy number.

645163110081 is a `hidden beast` number, since 6 + 4 + 5 + 1 + 631 + 10 + 0 + 8 + 1 = 666.

It is not a de Polignac number, because 645163110081 - 2⁵ = 645163110049 is a prime.

It is a super-2 number, since 2×645163110081² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (645163110083) 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, 46122216 + ... + 46136201.

It is an arithmetic number, because the mean of its divisors is an integer number (35058198840).

Almost surely, 2^645163110081 is an apocalyptic number.

It is an amenable number.

645163110081 is a deficient number, since it is larger than the sum of its proper divisors (476699252799).

645163110081 is a wasteful number, since it uses less digits than its factorization.

645163110081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92258470 (or 92258464 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 36.

The spelling of 645163110081 in words is "six hundred forty-five billion, one hundred sixty-three million, one hundred ten thousand, eighty-one".