921194375521 has 4 divisors (see below), whose sum is σ = 1052793572032. Its totient is φ = 789595179012.

The previous prime is 921194375417. The next prime is 921194375537. The reversal of 921194375521 is 125573491129.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 921194375521 - 2⁷ = 921194375393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (921194375561) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 65799598245 + ... + 65799598258.

It is an arithmetic number, because the mean of its divisors is an integer number (263198393008).

Almost surely, 2^921194375521 is an apocalyptic number.

It is an amenable number.

921194375521 is a deficient number, since it is larger than the sum of its proper divisors (131599196511).

921194375521 is a wasteful number, since it uses less digits than its factorization.

921194375521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131599196510.

The product of its digits is 680400, while the sum is 49.

The spelling of 921194375521 in words is "nine hundred twenty-one billion, one hundred ninety-four million, three hundred seventy-five thousand, five hundred twenty-one".