891555841 has 4 divisors (see below), whose sum is σ = 972606384. Its totient is φ = 810505300.

The previous prime is 891555839. The next prime is 891555883. The reversal of 891555841 is 148555198.

It is a happy number.

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 not a de Polignac number, because 891555841 - 2¹ = 891555839 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 891555791 and 891555800.

It is not an unprimeable number, because it can be changed into a prime (891555341) 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, 40525255 + ... + 40525276.

It is an arithmetic number, because the mean of its divisors is an integer number (243151596).

Almost surely, 2^891555841 is an apocalyptic number.

It is an amenable number.

891555841 is a deficient number, since it is larger than the sum of its proper divisors (81050543).

891555841 is a wasteful number, since it uses less digits than its factorization.

891555841 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81050542.

The product of its digits is 288000, while the sum is 46.

The square root of 891555841 is about 29858.9323486289. The cubic root of 891555841 is about 962.4603560666.

The spelling of 891555841 in words is "eight hundred ninety-one million, five hundred fifty-five thousand, eight hundred forty-one".