9961893391 has 4 divisors (see below), whose sum is σ = 9980307784. Its totient is φ = 9943479000.

The previous prime is 9961893373. The next prime is 9961893449. The reversal of 9961893391 is 1933981699.

9961893391 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 9961893391 - 2²³ = 9953504783 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9961893691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9206385 + ... + 9207466.

It is an arithmetic number, because the mean of its divisors is an integer number (2495076946).

Almost surely, 2^9961893391 is an apocalyptic number.

9961893391 is a deficient number, since it is larger than the sum of its proper divisors (18414393).

9961893391 is a wasteful number, since it uses less digits than its factorization.

9961893391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18414392.

The product of its digits is 2834352, while the sum is 58.

The square root of 9961893391 is about 99809.2850941234. The cubic root of 9961893391 is about 2151.6945998825.

The spelling of 9961893391 in words is "nine billion, nine hundred sixty-one million, eight hundred ninety-three thousand, three hundred ninety-one".