1212223221000 has 384 divisors, whose sum is σ = 4479916896000. Its totient is φ = 293207040000.

The previous prime is 1212223220987. The next prime is 1212223221029. The reversal of 1212223221000 is 1223222121.

1212223221000 is a `hidden beast` number, since 1 + 21 + 222 + 322 + 100 + 0 = 666.

It is a super-2 number, since 2×1212223221000² (a number of 25 digits) contains 22 as substring.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 44437365 + ... + 44464635.

It is an arithmetic number, because the mean of its divisors is an integer number (11666450250).

Almost surely, 2^{1212223221000} is an apocalyptic number.

1212223221000 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 1212223221000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2239958448000).

1212223221000 is an abundant number, since it is smaller than the sum of its proper divisors (3267693675000).

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

1212223221000 is a wasteful number, since it uses less digits than its factorization.

1212223221000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27758 (or 27741 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

Adding to 1212223221000 its reverse (1223222121), we get a palindrome (1213446443121).

The spelling of 1212223221000 in words is "one trillion, two hundred twelve billion, two hundred twenty-three million, two hundred twenty-one thousand".