919893910321 has 9 divisors (see below), whose sum is σ = 921923056299. Its totient is φ = 917869227000.

The previous prime is 919893910307. The next prime is 919893910333. The reversal of 919893910321 is 123019398919.

The square root of 919893910321 is 959111.

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

It can be written as a sum of positive squares in only one way, i.e., 730407820321 + 189486090000 = 854639^2 + 435300^2 .

It is not a de Polignac number, because 919893910321 - 2²³ = 919885521713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (919893910121) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 633971646 + ... + 633973096.

Almost surely, 2^919893910321 is an apocalyptic number.

919893910321 is the 959111-st square number.

919893910321 is the 479556-th centered octagonal number.

It is an amenable number.

919893910321 is a deficient number, since it is larger than the sum of its proper divisors (2029145978).

919893910321 is an frugal number, since it uses more digits than its factorization.

919893910321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4224 (or 2112 counting only the distinct ones).

The product of its (nonzero) digits is 944784, while the sum is 55.

The spelling of 919893910321 in words is "nine hundred nineteen billion, eight hundred ninety-three million, nine hundred ten thousand, three hundred twenty-one".