1663755678 has 96 divisors (see below), whose sum is σ = 4030021632. Its totient is φ = 492609600.

The previous prime is 1663755661. The next prime is 1663755689. The reversal of 1663755678 is 8765573661.

1663755678 is a `hidden beast` number, since 1 + 6 + 6 + 3 + 75 + 567 + 8 = 666.

Its product of digits (6350400) is a multiple of the sum of its prime factors (1350).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1530051 + ... + 1531137.

It is an arithmetic number, because the mean of its divisors is an integer number (41979392).

Almost surely, 2^1663755678 is an apocalyptic number.

1663755678 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1663755678, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2015010816).

1663755678 is an abundant number, since it is smaller than the sum of its proper divisors (2366265954).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1663755678 is a wasteful number, since it uses less digits than its factorization.

1663755678 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1350 (or 1347 counting only the distinct ones).

The product of its digits is 6350400, while the sum is 54.

The square root of 1663755678 is about 40789.1612809089. The cubic root of 1663755678 is about 1184.9404274918.

It can be divided in two parts, 166 and 3755678, that added together give a square (3755844 = 1938²).

The spelling of 1663755678 in words is "one billion, six hundred sixty-three million, seven hundred fifty-five thousand, six hundred seventy-eight".