891155939431 has 4 divisors (see below), whose sum is σ = 891159172992. Its totient is φ = 891152705872.

The previous prime is 891155939417. The next prime is 891155939447. The reversal of 891155939431 is 134939551198.

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 891155939431 - 2¹⁷ = 891155808359 is a prime.

It is a super-2 number, since 2×891155939431² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (891155939461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1160455 + ... + 1768888.

It is an arithmetic number, because the mean of its divisors is an integer number (222789793248).

Almost surely, 2^891155939431 is an apocalyptic number.

891155939431 is a deficient number, since it is larger than the sum of its proper divisors (3233561).

891155939431 is a wasteful number, since it uses less digits than its factorization.

891155939431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3233560.

The product of its digits is 5248800, while the sum is 58.

The spelling of 891155939431 in words is "eight hundred ninety-one billion, one hundred fifty-five million, nine hundred thirty-nine thousand, four hundred thirty-one".