61755220 has 48 divisors (see below), whose sum is σ = 141054480. Its totient is φ = 22616064.

The previous prime is 61755191. The next prime is 61755223. The reversal of 61755220 is 2255716.

It can be written as a sum of positive squares in 8 ways, for example, as 22867524 + 38887696 = 4782^2 + 6236^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61755223) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10126 + ... + 15034.

It is an arithmetic number, because the mean of its divisors is an integer number (2938635).

Almost surely, 2^61755220 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 61755220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (70527240).

61755220 is an abundant number, since it is smaller than the sum of its proper divisors (79299260).

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

61755220 is a wasteful number, since it uses less digits than its factorization.

61755220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4972 (or 4970 counting only the distinct ones).

The product of its (nonzero) digits is 4200, while the sum is 28.

The square root of 61755220 is about 7858.4489563781. The cubic root of 61755220 is about 395.2676069409.

The spelling of 61755220 in words is "sixty-one million, seven hundred fifty-five thousand, two hundred twenty".