645520515126 has 64 divisors (see below), whose sum is σ = 1366242508800. Its totient is φ = 202763584800.

The previous prime is 645520515121. The next prime is 645520515181. The reversal of 645520515126 is 621515025546.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645520515121) 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, 16963461 + ... + 17001471.

It is an arithmetic number, because the mean of its divisors is an integer number (21347539200).

Almost surely, 2^645520515126 is an apocalyptic number.

645520515126 is an abundant number, since it is smaller than the sum of its proper divisors (720721993674).

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

645520515126 is a wasteful number, since it uses less digits than its factorization.

645520515126 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38825.

The product of its (nonzero) digits is 360000, while the sum is 42.

The spelling of 645520515126 in words is "six hundred forty-five billion, five hundred twenty million, five hundred fifteen thousand, one hundred twenty-six".