1211994020 has 24 divisors (see below), whose sum is σ = 2565233664. Its totient is φ = 480979296.

The previous prime is 1211994019. The next prime is 1211994023. The reversal of 1211994020 is 204991121.

It is not an unprimeable number, because it can be changed into a prime (1211994023) 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, 236042 + ... + 241121.

It is an arithmetic number, because the mean of its divisors is an integer number (106884736).

Almost surely, 2^1211994020 is an apocalyptic number.

1211994020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1211994020 is an abundant number, since it is smaller than the sum of its proper divisors (1353239644).

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

1211994020 is a wasteful number, since it uses less digits than its factorization.

1211994020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 477299 (or 477297 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 29.

The square root of 1211994020 is about 34813.7044854465. The cubic root of 1211994020 is about 1066.1872687318.

The spelling of 1211994020 in words is "one billion, two hundred eleven million, nine hundred ninety-four thousand, twenty".