55061720 has 64 divisors (see below), whose sum is σ = 146491200. Its totient is φ = 18224640.

The previous prime is 55061693. The next prime is 55061723. The reversal of 55061720 is 2716055.

It is a super-3 number, since 3×55061720³ (a number of 24 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 55061720.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55061723) 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, 4730 + ... + 11510.

It is an arithmetic number, because the mean of its divisors is an integer number (2288925).

Almost surely, 2^55061720 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 55061720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (73245600).

55061720 is an abundant number, since it is smaller than the sum of its proper divisors (91429480).

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

55061720 is a wasteful number, since it uses less digits than its factorization.

55061720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6828 (or 6824 counting only the distinct ones).

The product of its (nonzero) digits is 2100, while the sum is 26.

The square root of 55061720 is about 7420.3584819064. The cubic root of 55061720 is about 380.4374463681.

Adding to 55061720 its reverse (2716055), we get a palindrome (57777775).

The spelling of 55061720 in words is "fifty-five million, sixty-one thousand, seven hundred twenty".