55985557 has 4 divisors (see below), whose sum is σ = 56072736. Its totient is φ = 55898380.

The previous prime is 55985549. The next prime is 55985563. The reversal of 55985557 is 75558955.

It is a happy number.

55985557 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 55985557 - 2³ = 55985549 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 55985557.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55985057) 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 3 ways as a sum of consecutive naturals, for example, 42619 + ... + 43912.

It is an arithmetic number, because the mean of its divisors is an integer number (14018184).

Almost surely, 2^55985557 is an apocalyptic number.

It is an amenable number.

55985557 is a deficient number, since it is larger than the sum of its proper divisors (87179).

55985557 is an equidigital number, since it uses as much as digits as its factorization.

55985557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87178.

The product of its digits is 1575000, while the sum is 49.

The square root of 55985557 is about 7482.3496977888. The cubic root of 55985557 is about 382.5533426966.

The spelling of 55985557 in words is "fifty-five million, nine hundred eighty-five thousand, five hundred fifty-seven".