891345840 has 320 divisors, whose sum is σ = 3479777280. Its totient is φ = 183352320.

The previous prime is 891345811. The next prime is 891345859. The reversal of 891345840 is 48543198.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 891345792 and 891345801.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2568547 + ... + 2568893.

It is an arithmetic number, because the mean of its divisors is an integer number (10874304).

Almost surely, 2^891345840 is an apocalyptic number.

891345840 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 891345840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1739888640).

891345840 is an abundant number, since it is smaller than the sum of its proper divisors (2588431440).

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

891345840 is a wasteful number, since it uses less digits than its factorization.

891345840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 520 (or 514 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 42.

The square root of 891345840 is about 29855.4155891356. The cubic root of 891345840 is about 962.3847827451.

The spelling of 891345840 in words is "eight hundred ninety-one million, three hundred forty-five thousand, eight hundred forty".