56781540 has 96 divisors (see below), whose sum is σ = 179262720. Its totient is φ = 14918400.

The previous prime is 56781523. The next prime is 56781551. The reversal of 56781540 is 4518765.

56781540 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 56781495 and 56781504.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 37600 + ... + 39080.

It is an arithmetic number, because the mean of its divisors is an integer number (1867320).

Almost surely, 2^56781540 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 56781540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89631360).

56781540 is an abundant number, since it is smaller than the sum of its proper divisors (122481180).

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

56781540 is a wasteful number, since it uses less digits than its factorization.

56781540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1570 (or 1562 counting only the distinct ones).

The product of its (nonzero) digits is 33600, while the sum is 36.

The square root of 56781540 is about 7535.3526792049. The cubic root of 56781540 is about 384.3578207670.

The spelling of 56781540 in words is "fifty-six million, seven hundred eighty-one thousand, five hundred forty".