1815212228 has 12 divisors (see below), whose sum is σ = 3184169772. Its totient is φ = 905449440.

The previous prime is 1815212221. The next prime is 1815212237. The reversal of 1815212228 is 8222125181.

It can be written as a sum of positive squares in 2 ways, for example, as 51380224 + 1763832004 = 7168^2 + 41998^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1815212194 and 1815212203.

It is not an unprimeable number, because it can be changed into a prime (1815212221) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 537275 + ... + 540642.

It is an arithmetic number, because the mean of its divisors is an integer number (265347481).

Almost surely, 2^1815212228 is an apocalyptic number.

It is an amenable number.

1815212228 is a deficient number, since it is larger than the sum of its proper divisors (1368957544).

1815212228 is a wasteful number, since it uses less digits than its factorization.

1815212228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1078342 (or 1078340 counting only the distinct ones).

The product of its digits is 5120, while the sum is 32.

The square root of 1815212228 is about 42605.3075097458. The cubic root of 1815212228 is about 1219.8575996116.

The spelling of 1815212228 in words is "one billion, eight hundred fifteen million, two hundred twelve thousand, two hundred twenty-eight".