1221233211000 has 384 divisors, whose sum is σ = 4624737024960. Its totient is φ = 288054144000.

The previous prime is 1221233210993. The next prime is 1221233211067. The reversal of 1221233211000 is 1123321221.

1221233211000 is a `hidden beast` number, since 1 + 221 + 2 + 332 + 110 + 0 + 0 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 3496302 + ... + 3829698.

Almost surely, 2^{1221233211000} is an apocalyptic number.

1221233211000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1221233211000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2312368512480).

1221233211000 is an abundant number, since it is smaller than the sum of its proper divisors (3403503813960).

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

1221233211000 is a wasteful number, since it uses less digits than its factorization.

1221233211000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333472 (or 333455 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 1221233211000 its reverse (1123321221), we get a palindrome (1222356532221).

The spelling of 1221233211000 in words is "one trillion, two hundred twenty-one billion, two hundred thirty-three million, two hundred eleven thousand".