1921375887984 has 360 divisors, whose sum is σ = 6617485680000. Its totient is φ = 517451058432.

The previous prime is 1921375887973. The next prime is 1921375888009. The reversal of 1921375887984 is 4897885731291.

1921375887984 is a `hidden beast` number, since 1 + 9 + 2 + 1 + 37 + 588 + 7 + 9 + 8 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 26642727 + ... + 26714745.

Almost surely, 2^{1921375887984} is an apocalyptic number.

1921375887984 is a gapful number since it is divisible by the number (14) 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 1921375887984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3308742840000).

1921375887984 is an abundant number, since it is smaller than the sum of its proper divisors (4696109792016).

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

1921375887984 is a wasteful number, since it uses less digits than its factorization.

1921375887984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72265 (or 72249 counting only the distinct ones).

The product of its digits is 243855360, while the sum is 72.

The spelling of 1921375887984 in words is "one trillion, nine hundred twenty-one billion, three hundred seventy-five million, eight hundred eighty-seven thousand, nine hundred eighty-four".