1211211201312 has 144 divisors (see below), whose sum is σ = 3975411690432. Its totient is φ = 342633945600.

The previous prime is 1211211201289. The next prime is 1211211201337. The reversal of 1211211201312 is 2131021121121.

It is a happy number.

1211211201312 is a `hidden beast` number, since 1 + 211 + 21 + 120 + 1 + 312 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2770638 + ... + 3177869.

It is an arithmetic number, because the mean of its divisors is an integer number (27607025628).

Almost surely, 2^{1211211201312} is an apocalyptic number.

1211211201312 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1211211201312 is an abundant number, since it is smaller than the sum of its proper divisors (2764200489120).

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

1211211201312 is a wasteful number, since it uses less digits than its factorization.

1211211201312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5948631 (or 5948620 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 18.

Adding to 1211211201312 its reverse (2131021121121), we get a palindrome (3342232322433).

The spelling of 1211211201312 in words is "one trillion, two hundred eleven billion, two hundred eleven million, two hundred one thousand, three hundred twelve".