1220321894400 has 2016 divisors, whose sum is σ = 5395122690048. Its totient is φ = 267544166400.

The previous prime is 1220321894347. The next prime is 1220321894423. The reversal of 1220321894400 is 44981230221.

1220321894400 is a `hidden beast` number, since 1 + 2 + 2 + 0 + 32 + 189 + 440 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (2016).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 10799308744 + ... + 10799308856.

It is an arithmetic number, because the mean of its divisors is an integer number (2676152128).

Almost surely, 2^{1220321894400} is an apocalyptic number.

1220321894400 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 1220321894400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2697561345024).

1220321894400 is an abundant number, since it is smaller than the sum of its proper divisors (4174800795648).

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

1220321894400 is an equidigital number, since it uses as much as digits as its factorization.

1220321894400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 202 (or 161 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The spelling of 1220321894400 in words is "one trillion, two hundred twenty billion, three hundred twenty-one million, eight hundred ninety-four thousand, four hundred".