645120422015 has 16 divisors (see below), whose sum is σ = 794204072928. Its totient is φ = 502893651456.

The previous prime is 645120421873. The next prime is 645120422027. The reversal of 645120422015 is 510224021546.

645120422015 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 645120422015 - 2³⁶ = 576400945279 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10617014 + ... + 10677603.

It is an arithmetic number, because the mean of its divisors is an integer number (49637754558).

Almost surely, 2^645120422015 is an apocalyptic number.

645120422015 is a deficient number, since it is larger than the sum of its proper divisors (149083650913).

645120422015 is a wasteful number, since it uses less digits than its factorization.

645120422015 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21294778.

The product of its (nonzero) digits is 19200, while the sum is 32.

The spelling of 645120422015 in words is "six hundred forty-five billion, one hundred twenty million, four hundred twenty-two thousand, fifteen".