55420640 has 48 divisors (see below), whose sum is σ = 142838640. Its totient is φ = 20152320.

The previous prime is 55420583. The next prime is 55420649. The reversal of 55420640 is 4602455.

55420640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55420649) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 13985 + ... + 17504.

It is an arithmetic number, because the mean of its divisors is an integer number (2975805).

Almost surely, 2^55420640 is an apocalyptic number.

It is an amenable number.

55420640 is an abundant number, since it is smaller than the sum of its proper divisors (87418000).

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

55420640 is a wasteful number, since it uses less digits than its factorization.

55420640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31515 (or 31507 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 26.

The square root of 55420640 is about 7444.5040130287. The cubic root of 55420640 is about 381.2622842947.

The spelling of 55420640 in words is "fifty-five million, four hundred twenty thousand, six hundred forty".