18361387968 has 336 divisors, whose sum is σ = 63693934080. Its totient is φ = 4560906240.

The previous prime is 18361387943. The next prime is 18361387997. The reversal of 18361387968 is 86978316381.

It is a tau number, because it is divible by the number of its divisors (336).

It is a super-2 number, since 2×18361387968² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3737898 + ... + 3742806.

It is an arithmetic number, because the mean of its divisors is an integer number (189565280).

Almost surely, 2^18361387968 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18361387968, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31846967040).

18361387968 is an abundant number, since it is smaller than the sum of its proper divisors (45332546112).

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

18361387968 is a wasteful number, since it uses less digits than its factorization.

18361387968 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4976 (or 4955 counting only the distinct ones).

The product of its digits is 10450944, while the sum is 60.

The spelling of 18361387968 in words is "eighteen billion, three hundred sixty-one million, three hundred eighty-seven thousand, nine hundred sixty-eight".