1921209075875 has 8 divisors (see below), whose sum is σ = 2397668926848. Its totient is φ = 1536967260600.

The previous prime is 1921209075859. The next prime is 1921209075881. The reversal of 1921209075875 is 5785709021291.

It is not a de Polignac number, because 1921209075875 - 2⁴ = 1921209075859 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1921209075875.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7684836179 + ... + 7684836428.

It is an arithmetic number, because the mean of its divisors is an integer number (299708615856).

Almost surely, 2^{1921209075875} is an apocalyptic number.

1921209075875 is a deficient number, since it is larger than the sum of its proper divisors (476459850973).

1921209075875 is an equidigital number, since it uses as much as digits as its factorization.

1921209075875 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15369672622 (or 15369672612 counting only the distinct ones).

The product of its (nonzero) digits is 3175200, while the sum is 56.

The spelling of 1921209075875 in words is "one trillion, nine hundred twenty-one billion, two hundred nine million, seventy-five thousand, eight hundred seventy-five".