55781830 has 32 divisors (see below), whose sum is σ = 108813600. Its totient is φ = 20588256.

The previous prime is 55781783. The next prime is 55781833. The reversal of 55781830 is 3818755.

55781830 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×55781830² = 6223225116297800, which contains 22 as substring.

It is a nialpdrome in base 13.

It is a self number, because there is not a number n which added to its sum of digits gives 55781830.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55781833) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 20701 + ... + 23239.

It is an arithmetic number, because the mean of its divisors is an integer number (3400425).

Almost surely, 2^55781830 is an apocalyptic number.

55781830 is a deficient number, since it is larger than the sum of its proper divisors (53031770).

55781830 is a wasteful number, since it uses less digits than its factorization.

55781830 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2585 (or 2559 counting only the distinct ones).

The product of its (nonzero) digits is 33600, while the sum is 37.

The square root of 55781830 is about 7468.7234518357. The cubic root of 55781830 is about 382.0887516160.

The spelling of 55781830 in words is "fifty-five million, seven hundred eighty-one thousand, eight hundred thirty".