20116555 has 4 divisors (see below), whose sum is σ = 24139872. Its totient is φ = 16093240.

The previous prime is 20116543. The next prime is 20116619. The reversal of 20116555 is 55561102.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 55561102 = 2 ⋅27780551.

It is not a de Polignac number, because 20116555 - 2¹⁵ = 20083787 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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, 2011651 + ... + 2011660.

It is an arithmetic number, because the mean of its divisors is an integer number (6034968).

Almost surely, 2^20116555 is an apocalyptic number.

20116555 is a deficient number, since it is larger than the sum of its proper divisors (4023317).

20116555 is an equidigital number, since it uses as much as digits as its factorization.

20116555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4023316.

The product of its (nonzero) digits is 1500, while the sum is 25.

The square root of 20116555 is about 4485.1482695670. The cubic root of 20116555 is about 271.9680388844.

Adding to 20116555 its reverse (55561102), we get a palindrome (75677657).

The spelling of 20116555 in words is "twenty million, one hundred sixteen thousand, five hundred fifty-five".