55021605 has 16 divisors (see below), whose sum is σ = 93213504. Its totient is φ = 27618560.

The previous prime is 55021583. The next prime is 55021619. The reversal of 55021605 is 50612055.

It is not a de Polignac number, because 55021605 - 2¹⁴ = 55005221 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 107631 + ... + 108140.

It is an arithmetic number, because the mean of its divisors is an integer number (5825844).

Almost surely, 2^55021605 is an apocalyptic number.

It is an amenable number.

55021605 is a deficient number, since it is larger than the sum of its proper divisors (38191899).

55021605 is a wasteful number, since it uses less digits than its factorization.

55021605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 215796.

The product of its (nonzero) digits is 1500, while the sum is 24.

The square root of 55021605 is about 7417.6549528810. The cubic root of 55021605 is about 380.3450351864.

It can be divided in two parts, 550 and 21605, that added together give a triangular number (22155 = T₂₁₀).

The spelling of 55021605 in words is "fifty-five million, twenty-one thousand, six hundred five".