1921994049600 has 315 divisors, whose sum is σ = 7066601665981. Its totient is φ = 512398656000.

The previous prime is 1921994049593. The next prime is 1921994049623. The reversal of 1921994049600 is 69404991291.

The square root of 1921994049600 is 1386360.

It is a perfect power (a square), and thus also a powerful number.

1921994049600 is a `hidden beast` number, since 1 + 9 + 21 + 9 + 9 + 4 + 0 + 4 + 9 + 600 = 666.

It can be written as a sum of positive squares in only one way, i.e., 691917857856 + 1230076191744 = 831816^2 + 1109088^2 .

It is a super-2 number, since 2×1921994049600² (a number of 25 digits) contains 22 as substring.

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

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 499087675 + ... + 499091525.

Almost surely, 2^{1921994049600} is an apocalyptic number.

1921994049600 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1921994049600 is the 1386360-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1921994049600

1921994049600 is an abundant number, since it is smaller than the sum of its proper divisors (5144607616381).

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

1921994049600 is an frugal number, since it uses more digits than its factorization.

1921994049600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7736 (or 3861 counting only the distinct ones).

The product of its (nonzero) digits is 1259712, while the sum is 54.

The spelling of 1921994049600 in words is "one trillion, nine hundred twenty-one billion, nine hundred ninety-four million, forty-nine thousand, six hundred".