1211000021120 has 64 divisors (see below), whose sum is σ = 3065343831000. Its totient is φ = 455905886208.

The previous prime is 1211000021117. The next prime is 1211000021129. The reversal of 1211000021120 is 211200001121.

It can be written as a sum of positive squares in 4 ways, for example, as 977076894784 + 233923126336 = 988472^2 + 483656^2 .

It is a tau number, because it is divible by the number of its divisors (64).

It is not an unprimeable number, because it can be changed into a prime (1211000021129) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 55641695 + ... + 55663454.

Almost surely, 2^{1211000021120} is an apocalyptic number.

1211000021120 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1211000021120 is an abundant number, since it is smaller than the sum of its proper divisors (1854343809880).

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

1211000021120 is a wasteful number, since it uses less digits than its factorization.

1211000021120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111305185 (or 111305173 counting only the distinct ones).

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

Adding to 1211000021120 its reverse (211200001121), we get a palindrome (1422200022241).

The spelling of 1211000021120 in words is "one trillion, two hundred eleven billion, twenty-one thousand, one hundred twenty".