18816979968 has 176 divisors, whose sum is σ = 55903733760. Its totient is φ = 6252429312.

The previous prime is 18816979967. The next prime is 18816979981. The reversal of 18816979968 is 86997961881.

It is a super-2 number, since 2×18816979968² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a junction number, because it is equal to n+sod(n) for n = 18816979896 and 18816979905.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18816979967) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10588296 + ... + 10590072.

Almost surely, 2^18816979968 is an apocalyptic number.

18816979968 is a gapful number since it is divisible by the number (18) 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 18816979968, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27951866880).

18816979968 is an abundant number, since it is smaller than the sum of its proper divisors (37086753792).

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

18816979968 is a wasteful number, since it uses less digits than its factorization.

18816979968 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2189 (or 2165 counting only the distinct ones).

The product of its digits is 94058496, while the sum is 72.

The spelling of 18816979968 in words is "eighteen billion, eight hundred sixteen million, nine hundred seventy-nine thousand, nine hundred sixty-eight".