645400836027 has 12 divisors (see below), whose sum is σ = 932283336504. Its totient is φ = 430249831200.

The previous prime is 645400836001. The next prime is 645400836029. The reversal of 645400836027 is 720638004546.

645400836027 is a `hidden beast` number, since 6 + 4 + 540 + 0 + 83 + 6 + 0 + 27 = 666.

It is not a de Polignac number, because 645400836027 - 2⁸ = 645400835771 is a prime.

It is a super-2 number, since 2×645400836027² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (645400836029) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1212349 + ... + 1661502.

It is an arithmetic number, because the mean of its divisors is an integer number (77690278042).

Almost surely, 2^645400836027 is an apocalyptic number.

645400836027 is a deficient number, since it is larger than the sum of its proper divisors (286882500477).

645400836027 is a wasteful number, since it uses less digits than its factorization.

645400836027 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2898810 (or 2898807 counting only the distinct ones).

The product of its (nonzero) digits is 967680, while the sum is 45.

The spelling of 645400836027 in words is "six hundred forty-five billion, four hundred million, eight hundred thirty-six thousand, twenty-seven".