645515555110513 has 16 divisors (see below), whose sum is σ = 652716787121920. Its totient is φ = 638359265952000.

The previous prime is 645515555110501. The next prime is 645515555110529. The reversal of 645515555110513 is 315011555515546.

It is a cyclic number.

It is not a de Polignac number, because 645515555110513 - 2³³ = 645506965175921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (645515555116513) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19345453 + ... + 40807813.

It is an arithmetic number, because the mean of its divisors is an integer number (40794799195120).

Almost surely, 2^{645515555110513} is an apocalyptic number.

It is an amenable number.

645515555110513 is a deficient number, since it is larger than the sum of its proper divisors (7201232011407).

645515555110513 is a wasteful number, since it uses less digits than its factorization.

645515555110513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21463408.

The product of its (nonzero) digits is 5625000, while the sum is 52.

The spelling of 645515555110513 in words is "six hundred forty-five trillion, five hundred fifteen billion, five hundred fifty-five million, one hundred ten thousand, five hundred thirteen".