2220815556 has 30 divisors (see below), whose sum is σ = 5805651390. Its totient is φ = 740271744.

The previous prime is 2220815543. The next prime is 2220815557. The reversal of 2220815556 is 6555180222.

It is a happy number.

2220815556 is a `hidden beast` number, since 2 + 2 + 20 + 81 + 5 + 556 = 666.

It can be written as a sum of positive squares in only one way, i.e., 2005606656 + 215208900 = 44784^2 + 14670^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 2220815556.

It is not an unprimeable number, because it can be changed into a prime (2220815557) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 3426861 + ... + 3427508.

It is an arithmetic number, because the mean of its divisors is an integer number (193521713).

Almost surely, 2^2220815556 is an apocalyptic number.

It is an amenable number.

2220815556 is an abundant number, since it is smaller than the sum of its proper divisors (3584835834).

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

2220815556 is a wasteful number, since it uses less digits than its factorization.

2220815556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6854385 (or 6854374 counting only the distinct ones).

The product of its (nonzero) digits is 48000, while the sum is 36.

The square root of 2220815556 is about 47125.5297689055. The cubic root of 2220815556 is about 1304.6804766675.

Adding to 2220815556 its reverse (6555180222), we get a palindrome (8775995778).

The spelling of 2220815556 in words is "two billion, two hundred twenty million, eight hundred fifteen thousand, five hundred fifty-six".