1221603748992 has 768 divisors, whose sum is σ = 4095846720000. Its totient is φ = 357992110080.

The previous prime is 1221603748903. The next prime is 1221603748993. The reversal of 1221603748992 is 2998473061221.

1221603748992 is a `hidden beast` number, since 1 + 2 + 21 + 603 + 7 + 4 + 8 + 9 + 9 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (1221603748993) by changing a digit.

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, 1653049359 + ... + 1653050097.

It is an arithmetic number, because the mean of its divisors is an integer number (5333133750).

Almost surely, 2^{1221603748992} is an apocalyptic number.

1221603748992 is a gapful number since it is divisible by the number (12) 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 1221603748992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2047923360000).

1221603748992 is an abundant number, since it is smaller than the sum of its proper divisors (2874242971008).

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

1221603748992 is a wasteful number, since it uses less digits than its factorization.

1221603748992 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 910 (or 881 counting only the distinct ones).

The product of its (nonzero) digits is 2612736, while the sum is 54.

The spelling of 1221603748992 in words is "one trillion, two hundred twenty-one billion, six hundred three million, seven hundred forty-eight thousand, nine hundred ninety-two".