61671220 has 48 divisors (see below), whose sum is σ = 140308560. Its totient is φ = 22634496.

The previous prime is 61671217. The next prime is 61671221. The reversal of 61671220 is 2217616.

61671220 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 8 ways, for example, as 268324 + 61402896 = 518^2 + 7836^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61671221) 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, 49566 + ... + 50794.

It is an arithmetic number, because the mean of its divisors is an integer number (2923095).

Almost surely, 2^61671220 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 61671220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (70154280).

61671220 is an abundant number, since it is smaller than the sum of its proper divisors (78637340).

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

61671220 is a wasteful number, since it uses less digits than its factorization.

61671220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1444 (or 1442 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 25.

The square root of 61671220 is about 7853.1025715955. The cubic root of 61671220 is about 395.0883101167.

Adding to 61671220 its reverse (2217616), we get a palindrome (63888836).

The spelling of 61671220 in words is "sixty-one million, six hundred seventy-one thousand, two hundred twenty".