1211021120 has 28 divisors (see below), whose sum is σ = 2883744804. Its totient is φ = 484408320.

The previous prime is 1211021117. The next prime is 1211021143. The reversal of 1211021120 is 211201121.

It can be written as a sum of positive squares in 2 ways, for example, as 151388416 + 1059632704 = 12304^2 + 32552^2 .

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, 1891901 + ... + 1892540.

Almost surely, 2^1211021120 is an apocalyptic number.

1211021120 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1211021120 is an abundant number, since it is smaller than the sum of its proper divisors (1672723684).

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

1211021120 is an equidigital number, since it uses as much as digits as its factorization.

1211021120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3784458 (or 3784448 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 11.

The square root of 1211021120 is about 34799.7287345749. The cubic root of 1211021120 is about 1065.9019066879.

Adding to 1211021120 its reverse (211201121), we get a palindrome (1422222241).

The spelling of 1211021120 in words is "one billion, two hundred eleven million, twenty-one thousand, one hundred twenty".