18778001856 has 112 divisors (see below), whose sum is σ = 51021630240. Its totient is φ = 6092881920.

The previous prime is 18778001839. The next prime is 18778001947. The reversal of 18778001856 is 65810087781.

It is a super-2 number, since 2×18778001856² (a number of 21 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (51) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 18778001799 and 18778001808.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1127800 + ... + 1144328.

It is an arithmetic number, because the mean of its divisors is an integer number (455550270).

Almost surely, 2^18778001856 is an apocalyptic number.

18778001856 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 18778001856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25510815120).

18778001856 is an abundant number, since it is smaller than the sum of its proper divisors (32243628384).

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

18778001856 is a wasteful number, since it uses less digits than its factorization.

18778001856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16702 (or 16692 counting only the distinct ones).

The product of its (nonzero) digits is 752640, while the sum is 51.

The spelling of 18778001856 in words is "eighteen billion, seven hundred seventy-eight million, one thousand, eight hundred fifty-six".