61641216 has 320 divisors, whose sum is σ = 229152000. Its totient is φ = 16257024.

The previous prime is 61641199. The next prime is 61641227. The reversal of 61641216 is 61214616.

61641216 is a `hidden beast` number, since 6 + 1 + 641 + 2 + 16 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a nude number because it is divisible by every one of its digits and also a Zuckerman number because it is divisible by the product of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 61641216.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4741626 + ... + 4741638.

It is an arithmetic number, because the mean of its divisors is an integer number (716100).

Almost surely, 2^61641216 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 61641216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (114576000).

61641216 is an abundant number, since it is smaller than the sum of its proper divisors (167510784).

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

61641216 is an equidigital number, since it uses as much as digits as its factorization.

61641216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61 (or 25 counting only the distinct ones).

The product of its digits is 1728, while the sum is 27.

The square root of 61641216 is about 7851.1920114082. The cubic root of 61641216 is about 395.0242275371.

The spelling of 61641216 in words is "sixty-one million, six hundred forty-one thousand, two hundred sixteen".