55405685 has 4 divisors (see below), whose sum is σ = 66486828. Its totient is φ = 44324544.

The previous prime is 55405673. The next prime is 55405699. The reversal of 55405685 is 58650455.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 58650455 = 5 ⋅11730091.

It can be written as a sum of positive squares in 2 ways, for example, as 26234884 + 29170801 = 5122^2 + 5401^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55405685 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5540564 + ... + 5540573.

It is an arithmetic number, because the mean of its divisors is an integer number (16621707).

Almost surely, 2^55405685 is an apocalyptic number.

It is an amenable number.

55405685 is a deficient number, since it is larger than the sum of its proper divisors (11081143).

55405685 is a wasteful number, since it uses less digits than its factorization.

55405685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11081142.

The product of its (nonzero) digits is 120000, while the sum is 38.

The square root of 55405685 is about 7443.4995129979. The cubic root of 55405685 is about 381.2279872626.

The spelling of 55405685 in words is "fifty-five million, four hundred five thousand, six hundred eighty-five".