211155005560 has 64 divisors (see below), whose sum is σ = 504034876800. Its totient is φ = 79337342976.

The previous prime is 211155005531. The next prime is 211155005561. The reversal of 211155005560 is 65500551112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211155005561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 41089 + ... + 651151.

It is an arithmetic number, because the mean of its divisors is an integer number (7875544950).

Almost surely, 2^211155005560 is an apocalyptic number.

211155005560 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 211155005560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (252017438400).

211155005560 is an abundant number, since it is smaller than the sum of its proper divisors (292879871240).

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

211155005560 is a wasteful number, since it uses less digits than its factorization.

211155005560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 610600 (or 610596 counting only the distinct ones).

The product of its (nonzero) digits is 7500, while the sum is 31.

Adding to 211155005560 its reverse (65500551112), we get a palindrome (276655556672).

The spelling of 211155005560 in words is "two hundred eleven billion, one hundred fifty-five million, five thousand, five hundred sixty".