1921729828800 has 672 divisors, whose sum is σ = 6874533652480. Its totient is φ = 468202291200.

The previous prime is 1921729828783. The next prime is 1921729828807. The reversal of 1921729828800 is 88289271291.

It is a Harshad number since it is a multiple of its sum of digits (57).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1921729828807) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 952765392 + ... + 952767408.

Almost surely, 2^{1921729828800} is an apocalyptic number.

1921729828800 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 1921729828800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3437266826240).

1921729828800 is an abundant number, since it is smaller than the sum of its proper divisors (4952803823680).

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

1921729828800 is a wasteful number, since it uses less digits than its factorization.

1921729828800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2429 (or 2414 counting only the distinct ones).

The product of its (nonzero) digits is 2322432, while the sum is 57.

The spelling of 1921729828800 in words is "one trillion, nine hundred twenty-one billion, seven hundred twenty-nine million, eight hundred twenty-eight thousand, eight hundred".