9921872194 has 8 divisors (see below), whose sum is σ = 16027639740. Its totient is φ = 4579325616.

The previous prime is 9921872179. The next prime is 9921872251. The reversal of 9921872194 is 4912781299.

It can be written as a sum of positive squares in 2 ways, for example, as 9358047169 + 563825025 = 96737^2 + 23745^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 190805209 + ... + 190805260.

Almost surely, 2^9921872194 is an apocalyptic number.

9921872194 is a deficient number, since it is larger than the sum of its proper divisors (6105767546).

9921872194 is a wasteful number, since it uses less digits than its factorization.

9921872194 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 381610484.

The product of its digits is 653184, while the sum is 52.

The square root of 9921872194 is about 99608.5949805538. The cubic root of 9921872194 is about 2148.8093060167.

The spelling of 9921872194 in words is "nine billion, nine hundred twenty-one million, eight hundred seventy-two thousand, one hundred ninety-four".