891449944199 has 4 divisors (see below), whose sum is σ = 891829125600. Its totient is φ = 891070762800.

The previous prime is 891449944117. The next prime is 891449944201. The reversal of 891449944199 is 991449944198.

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 891449944199 - 2³⁶ = 822730467463 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 (891449904199) 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, 189587174 + ... + 189591875.

It is an arithmetic number, because the mean of its divisors is an integer number (222957281400).

Almost surely, 2^891449944199 is an apocalyptic number.

891449944199 is a deficient number, since it is larger than the sum of its proper divisors (379181401).

891449944199 is a wasteful number, since it uses less digits than its factorization.

891449944199 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 379181400.

The product of its digits is 120932352, while the sum is 71.

Subtracting 891449944199 from its reverse (991449944198), we obtain a palindrome (99999999999).

The spelling of 891449944199 in words is "eight hundred ninety-one billion, four hundred forty-nine million, nine hundred forty-four thousand, one hundred ninety-nine".