57161780 has 48 divisors (see below), whose sum is σ = 130524240. Its totient is φ = 20901888.

The previous prime is 57161779. The next prime is 57161789. The reversal of 57161780 is 8716175.

It can be written as a sum of positive squares in 8 ways, for example, as 38416 + 57123364 = 196^2 + 7558^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 57161780.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (57161789) 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, 27332 + ... + 29348.

It is an arithmetic number, because the mean of its divisors is an integer number (2719255).

Almost surely, 2^57161780 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 57161780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (65262120).

57161780 is an abundant number, since it is smaller than the sum of its proper divisors (73362460).

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

57161780 is a wasteful number, since it uses less digits than its factorization.

57161780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2148 (or 2146 counting only the distinct ones).

The product of its (nonzero) digits is 11760, while the sum is 35.

The square root of 57161780 is about 7560.5409859348. The cubic root of 57161780 is about 385.2138689169.

The spelling of 57161780 in words is "fifty-seven million, one hundred sixty-one thousand, seven hundred eighty".