891221760 has 432 divisors, whose sum is σ = 3629310048. Its totient is φ = 199065600.

The previous prime is 891221743. The next prime is 891221761. The reversal of 891221760 is 67122198.

891221760 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (891221761) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1647090 + ... + 1647630.

Almost surely, 2^891221760 is an apocalyptic number.

891221760 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 891221760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1814655024).

891221760 is an abundant number, since it is smaller than the sum of its proper divisors (2738088288).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

891221760 is a wasteful number, since it uses less digits than its factorization.

891221760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 592 (or 575 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 36.

The square root of 891221760 is about 29853.3375018607. The cubic root of 891221760 is about 962.3401243421.

The spelling of 891221760 in words is "eight hundred ninety-one million, two hundred twenty-one thousand, seven hundred sixty".