9991849 has 4 divisors (see below), whose sum is σ = 11419264. Its totient is φ = 8564436.

The previous prime is 9991847. The next prime is 9991879. The reversal of 9991849 is 9481999.

9991849 is digitally balanced in base 2, base 3 and base 8, because in such bases it contains all the possibile digits an equal number of times.

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 9991849 - 2¹ = 9991847 is a prime.

It is a Duffinian number.

9991849 is strictly pandigital in base 8.

It is not an unprimeable number, because it can be changed into a prime (9991847) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 713697 + ... + 713710.

It is an arithmetic number, because the mean of its divisors is an integer number (2854816).

Almost surely, 2^9991849 is an apocalyptic number.

It is an amenable number.

9991849 is a deficient number, since it is larger than the sum of its proper divisors (1427415).

9991849 is a wasteful number, since it uses less digits than its factorization.

9991849 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1427414.

The product of its digits is 209952, while the sum is 49.

The square root of 9991849 is about 3160.9886111785. The cubic root of 9991849 is about 215.3849171012.

The spelling of 9991849 in words is "nine million, nine hundred ninety-one thousand, eight hundred forty-nine".