13778961408 has 176 divisors, whose sum is σ = 41371671360. Its totient is φ = 4529405952.

The previous prime is 13778961403. The next prime is 13778961419. The reversal of 13778961408 is 80416987731.

13778961408 is a `hidden beast` number, since 13 + 7 + 7 + 8 + 9 + 614 + 0 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (13778961401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2014891 + ... + 2021717.

Almost surely, 2^13778961408 is an apocalyptic number.

13778961408 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 13778961408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20685835680).

13778961408 is an abundant number, since it is smaller than the sum of its proper divisors (27592709952).

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

13778961408 is an equidigital number, since it uses as much as digits as its factorization.

13778961408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6929 (or 6905 counting only the distinct ones).

The product of its (nonzero) digits is 2032128, while the sum is 54.

The spelling of 13778961408 in words is "thirteen billion, seven hundred seventy-eight million, nine hundred sixty-one thousand, four hundred eight".