18036778656 has 288 divisors, whose sum is σ = 53683064064. Its totient is φ = 5267404800.

The previous prime is 18036778649. The next prime is 18036778657. The reversal of 18036778656 is 65687763081.

It is a junction number, because it is equal to n+sod(n) for n = 18036778596 and 18036778605.

It is not an unprimeable number, because it can be changed into a prime (18036778657) 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, 254039101 + ... + 254039171.

It is an arithmetic number, because the mean of its divisors is an integer number (186399528).

Almost surely, 2^18036778656 is an apocalyptic number.

18036778656 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18036778656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26841532032).

18036778656 is an abundant number, since it is smaller than the sum of its proper divisors (35646285408).

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

18036778656 is a wasteful number, since it uses less digits than its factorization.

18036778656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 276 (or 197 counting only the distinct ones).

The product of its (nonzero) digits is 10160640, while the sum is 57.

The spelling of 18036778656 in words is "eighteen billion, thirty-six million, seven hundred seventy-eight thousand, six hundred fifty-six".