1811218272 has 24 divisors (see below), whose sum is σ = 4754448216. Its totient is φ = 603739392.

The previous prime is 1811218243. The next prime is 1811218313. The reversal of 1811218272 is 2728121181.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (24).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9433333 + ... + 9433524.

It is an arithmetic number, because the mean of its divisors is an integer number (198102009).

Almost surely, 2^1811218272 is an apocalyptic number.

1811218272 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1811218272 is an abundant number, since it is smaller than the sum of its proper divisors (2943229944).

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

1811218272 is a wasteful number, since it uses less digits than its factorization.

1811218272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18866870 (or 18866862 counting only the distinct ones).

The product of its digits is 3584, while the sum is 33.

The square root of 1811218272 is about 42558.4101206800. The cubic root of 1811218272 is about 1218.9622708345.

The spelling of 1811218272 in words is "one billion, eight hundred eleven million, two hundred eighteen thousand, two hundred seventy-two".