1221381405000 has 960 divisors, whose sum is σ = 4500134496000. Its totient is φ = 298045440000.

The previous prime is 1221381404993. The next prime is 1221381405031. The reversal of 1221381405000 is 5041831221.

1221381405000 is a `hidden beast` number, since 1 + 2 + 2 + 13 + 8 + 140 + 500 + 0 = 666.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 239 ways as a sum of consecutive naturals, for example, 6137594901 + ... + 6137595099.

It is an arithmetic number, because the mean of its divisors is an integer number (4687640100).

Almost surely, 2^{1221381405000} is an apocalyptic number.

1221381405000 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 1221381405000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2250067248000).

1221381405000 is an abundant number, since it is smaller than the sum of its proper divisors (3278753091000).

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

1221381405000 is a wasteful number, since it uses less digits than its factorization.

1221381405000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 432 (or 410 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

The spelling of 1221381405000 in words is "one trillion, two hundred twenty-one billion, three hundred eighty-one million, four hundred five thousand".