1211440220 has 12 divisors (see below), whose sum is σ = 2544024504. Its totient is φ = 484576080.

The previous prime is 1211440193. The next prime is 1211440231. The reversal of 1211440220 is 220441121.

It is a super-3 number, since 3×1211440220³ (a number of 28 digits) contains 333 as substring.

It is a congruent 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, 30285986 + ... + 30286025.

It is an arithmetic number, because the mean of its divisors is an integer number (212002042).

Almost surely, 2^1211440220 is an apocalyptic number.

1211440220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1211440220 is an abundant number, since it is smaller than the sum of its proper divisors (1332584284).

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

1211440220 is a wasteful number, since it uses less digits than its factorization.

1211440220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60572020 (or 60572018 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

The square root of 1211440220 is about 34805.7498123514. The cubic root of 1211440220 is about 1066.0248519610.

Adding to 1211440220 its reverse (220441121), we get a palindrome (1431881341).

Subtracting from 1211440220 its reverse (220441121), we obtain a palindrome (990999099).

The spelling of 1211440220 in words is "one billion, two hundred eleven million, four hundred forty thousand, two hundred twenty".