18638778201600 has 960 divisors, whose sum is σ = 65743636780800. Its totient is φ = 4641584578560.

The previous prime is 18638778201583. The next prime is 18638778201601. The reversal of 18638778201600 is 610287783681.

It is a tau number, because it is divible by the number of its divisors (960).

It is a Harshad number since it is a multiple of its sum of digits (57).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18638778201601) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 20063269936 + ... + 20063270864.

It is an arithmetic number, because the mean of its divisors is an integer number (68482954980).

Almost surely, 2^{18638778201600} is an apocalyptic number.

18638778201600 is a gapful number since it is divisible by the number (10) 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 18638778201600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32871818390400).

18638778201600 is an abundant number, since it is smaller than the sum of its proper divisors (47104858579200).

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

18638778201600 is a wasteful number, since it uses less digits than its factorization.

18638778201600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1343 (or 1322 counting only the distinct ones).

The product of its (nonzero) digits is 5419008, while the sum is 57.

The spelling of 18638778201600 in words is "eighteen trillion, six hundred thirty-eight billion, seven hundred seventy-eight million, two hundred one thousand, six hundred".