16278393663 has 80 divisors (see below), whose sum is σ = 28823044096. Its totient is φ = 8959351680.

The previous prime is 16278393661. The next prime is 16278393667. The reversal of 16278393663 is 36639387261.

16278393663 is a `hidden beast` number, since 1 + 6 + 278 + 3 + 9 + 366 + 3 = 666.

It is not a de Polignac number, because 16278393663 - 2¹ = 16278393661 is a prime.

It is a super-2 number, since 2×16278393663² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16278393661) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 3917595 + ... + 3921747.

Almost surely, 2^16278393663 is an apocalyptic number.

16278393663 is a deficient number, since it is larger than the sum of its proper divisors (12544650433).

16278393663 is a wasteful number, since it uses less digits than its factorization.

16278393663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4426 (or 4417 counting only the distinct ones).

The product of its digits is 5878656, while the sum is 54.

The spelling of 16278393663 in words is "sixteen billion, two hundred seventy-eight million, three hundred ninety-three thousand, six hundred sixty-three".