849198991 has 4 divisors (see below), whose sum is σ = 849769272. Its totient is φ = 848628712.

The previous prime is 849198989. The next prime is 849199003. The reversal of 849198991 is 199891948.

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 849198991 - 2¹ = 849198989 is a prime.

It is a super-2 number, since 2×849198991² = 1442277852630836162, which contains 22 as substring.

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (849192991) 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, 282901 + ... + 285886.

It is an arithmetic number, because the mean of its divisors is an integer number (212442318).

Almost surely, 2^849198991 is an apocalyptic number.

849198991 is a deficient number, since it is larger than the sum of its proper divisors (570281).

849198991 is a wasteful number, since it uses less digits than its factorization.

849198991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 570280.

The product of its digits is 1679616, while the sum is 58.

The square root of 849198991 is about 29141.0190453251. The cubic root of 849198991 is about 946.9705866549.

The spelling of 849198991 in words is "eight hundred forty-nine million, one hundred ninety-eight thousand, nine hundred ninety-one".