618561856815 has 16 divisors (see below), whose sum is σ = 1131084538368. Its totient is φ = 282771134496.

The previous prime is 618561856807. The next prime is 618561856841. The reversal of 618561856815 is 518658165816.

It is not a de Polignac number, because 618561856815 - 2³ = 618561856807 is a prime.

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, 2945532547 + ... + 2945532756.

It is an arithmetic number, because the mean of its divisors is an integer number (70692783648).

Almost surely, 2^618561856815 is an apocalyptic number.

618561856815 is a deficient number, since it is larger than the sum of its proper divisors (512522681553).

618561856815 is a wasteful number, since it uses less digits than its factorization.

618561856815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5891065318.

The product of its digits is 13824000, while the sum is 60.

The spelling of 618561856815 in words is "six hundred eighteen billion, five hundred sixty-one million, eight hundred fifty-six thousand, eight hundred fifteen".