55497780 has 144 divisors (see below), whose sum is σ = 186483024. Its totient is φ = 13271040.

The previous prime is 55497763. The next prime is 55497811. The reversal of 55497780 is 8779455.

55497780 = 70² + 71² + ... + 550².

55497780 is a `hidden beast` number, since 554 + 97 + 7 + 8 + 0 = 666.

55497780 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 2090916 + 53406864 = 1446^2 + 7308^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 86260 + ... + 86900.

It is an arithmetic number, because the mean of its divisors is an integer number (1295021).

Almost surely, 2^55497780 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 55497780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (93241512).

55497780 is an abundant number, since it is smaller than the sum of its proper divisors (130985244).

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

55497780 is a wasteful number, since it uses less digits than its factorization.

55497780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 706 (or 701 counting only the distinct ones).

The product of its (nonzero) digits is 352800, while the sum is 45.

The square root of 55497780 is about 7449.6832147414. The cubic root of 55497780 is about 381.4390953024.

The spelling of 55497780 in words is "fifty-five million, four hundred ninety-seven thousand, seven hundred eighty".