1212120211985 has 4 divisors (see below), whose sum is σ = 1454544254388. Its totient is φ = 969696169584.

The previous prime is 1212120211933. The next prime is 1212120212011. The reversal of 1212120211985 is 5891120212121.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 947961218689 + 264158993296 = 973633^2 + 513964^2 .

It is a cyclic number.

It is not a de Polignac number, because 1212120211985 - 2³⁶ = 1143400735249 is a prime.

It is a super-2 number, since 2×1212120211985² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon 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, 121212021194 + ... + 121212021203.

It is an arithmetic number, because the mean of its divisors is an integer number (363636063597).

Almost surely, 2^{1212120211985} is an apocalyptic number.

It is an amenable number.

1212120211985 is a deficient number, since it is larger than the sum of its proper divisors (242424042403).

1212120211985 is an equidigital number, since it uses as much as digits as its factorization.

1212120211985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 242424042402.

The product of its (nonzero) digits is 5760, while the sum is 35.

The spelling of 1212120211985 in words is "one trillion, two hundred twelve billion, one hundred twenty million, two hundred eleven thousand, nine hundred eighty-five".