16778809908 has 144 divisors (see below), whose sum is σ = 52348161600. Its totient is φ = 4628594880.

The previous prime is 16778809897. The next prime is 16778809919. The reversal of 16778809908 is 80990887761.

It is an interprime number because it is at equal distance from previous prime (16778809897) and next prime (16778809919).

It is a Harshad number since it is a multiple of its sum of digits (63).

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, 98803 + ... + 208133.

It is an arithmetic number, because the mean of its divisors is an integer number (363528900).

Almost surely, 2^16778809908 is an apocalyptic number.

16778809908 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 16778809908, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26174080800).

16778809908 is an abundant number, since it is smaller than the sum of its proper divisors (35569351692).

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

16778809908 is a wasteful number, since it uses less digits than its factorization.

16778809908 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109387 (or 109372 counting only the distinct ones).

The product of its (nonzero) digits is 12192768, while the sum is 63.

The spelling of 16778809908 in words is "sixteen billion, seven hundred seventy-eight million, eight hundred nine thousand, nine hundred eight".