7776381440 has 160 divisors (see below), whose sum is σ = 19555373376. Its totient is φ = 2962391040.

The previous prime is 7776381421. The next prime is 7776381491. The reversal of 7776381440 is 441836777.

It is a tau number, because it is divible by the number of its divisors (160).

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, 4512419 + ... + 4514141.

Almost surely, 2^7776381440 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 7776381440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (9777686688).

7776381440 is an abundant number, since it is smaller than the sum of its proper divisors (11778991936).

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

7776381440 is a wasteful number, since it uses less digits than its factorization.

7776381440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1830 (or 1814 counting only the distinct ones).

The product of its (nonzero) digits is 790272, while the sum is 47.

The square root of 7776381440 is about 88183.7935223928. The cubic root of 7776381440 is about 1981.1887430234.

The spelling of 7776381440 in words is "seven billion, seven hundred seventy-six million, three hundred eighty-one thousand, four hundred forty".