61305220 has 12 divisors (see below), whose sum is σ = 128741004. Its totient is φ = 24522080.

The previous prime is 61305187. The next prime is 61305221. The reversal of 61305220 is 2250316.

It is a happy number.

61305220 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 40729924 + 20575296 = 6382^2 + 4536^2 .

It is not an unprimeable number, because it can be changed into a prime (61305221) 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 3 ways as a sum of consecutive naturals, for example, 1532611 + ... + 1532650.

It is an arithmetic number, because the mean of its divisors is an integer number (10728417).

Almost surely, 2^61305220 is an apocalyptic number.

It is an amenable number.

61305220 is an abundant number, since it is smaller than the sum of its proper divisors (67435784).

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

61305220 is a wasteful number, since it uses less digits than its factorization.

61305220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3065270 (or 3065268 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 19.

The square root of 61305220 is about 7829.7650028593. The cubic root of 61305220 is about 394.3051823986.

Adding to 61305220 its reverse (2250316), we get a palindrome (63555536).

The spelling of 61305220 in words is "sixty-one million, three hundred five thousand, two hundred twenty".