55640784 has 80 divisors (see below), whose sum is σ = 151053824. Its totient is φ = 17625600.

The previous prime is 55640773. The next prime is 55640789. The reversal of 55640784 is 48704655.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55640789) 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, 90462 + ... + 91074.

Almost surely, 2^55640784 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 55640784, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (75526912).

55640784 is an abundant number, since it is smaller than the sum of its proper divisors (95413040).

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

55640784 is a wasteful number, since it uses less digits than its factorization.

55640784 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 716 (or 710 counting only the distinct ones).

The product of its (nonzero) digits is 134400, while the sum is 39.

The square root of 55640784 is about 7459.2750317977. The cubic root of 55640784 is about 381.7664389169.

The spelling of 55640784 in words is "fifty-five million, six hundred forty thousand, seven hundred eighty-four".