1921195916640 has 3072 divisors, whose sum is σ = 9672929280000. Its totient is φ = 342910402560.

The previous prime is 1921195916639. The next prime is 1921195916693. The reversal of 1921195916640 is 466195911291.

1921195916640 is a `hidden beast` number, since 1 + 9 + 2 + 1 + 1 + 9 + 591 + 6 + 6 + 40 = 666.

It is a super-2 number, since 2×1921195916640² (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 congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 511 ways as a sum of consecutive naturals, for example, 5504859186 + ... + 5504859534.

It is an arithmetic number, because the mean of its divisors is an integer number (3148740000).

Almost surely, 2^{1921195916640} is an apocalyptic number.

1921195916640 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 1921195916640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4836464640000).

1921195916640 is an abundant number, since it is smaller than the sum of its proper divisors (7751733363360).

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

1921195916640 is a wasteful number, since it uses less digits than its factorization.

1921195916640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 490 (or 476 counting only the distinct ones).

The product of its (nonzero) digits is 1049760, while the sum is 54.

The spelling of 1921195916640 in words is "one trillion, nine hundred twenty-one billion, one hundred ninety-five million, nine hundred sixteen thousand, six hundred forty".