16861653865 has 48 divisors (see below), whose sum is σ = 23987715840. Its totient is φ = 11343171840.

The previous prime is 16861653863. The next prime is 16861653869. The reversal of 16861653865 is 56835616861.

It is not a de Polignac number, because 16861653865 - 2¹ = 16861653863 is a prime.

It is not an unprimeable number, because it can be changed into a prime (16861653863) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2853504 + ... + 2859406.

It is an arithmetic number, because the mean of its divisors is an integer number (499744080).

Almost surely, 2^16861653865 is an apocalyptic number.

It is an amenable number.

16861653865 is a deficient number, since it is larger than the sum of its proper divisors (7126061975).

16861653865 is a wasteful number, since it uses less digits than its factorization.

16861653865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6142 (or 6135 counting only the distinct ones).

The product of its digits is 6220800, while the sum is 55.

The spelling of 16861653865 in words is "sixteen billion, eight hundred sixty-one million, six hundred fifty-three thousand, eight hundred sixty-five".