891239040 has 192 divisors, whose sum is σ = 3093292800. Its totient is φ = 236451840.

The previous prime is 891239039. The next prime is 891239131. The reversal of 891239040 is 40932198.

It is a tau number, because it is divible by the number of its divisors (192).

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

It is a junction number, because it is equal to n+sod(n) for n = 891238986 and 891239004.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2067625 + ... + 2068055.

It is an arithmetic number, because the mean of its divisors is an integer number (16110900).

Almost surely, 2^891239040 is an apocalyptic number.

891239040 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 891239040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1546646400).

891239040 is an abundant number, since it is smaller than the sum of its proper divisors (2202053760).

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

891239040 is a wasteful number, since it uses less digits than its factorization.

891239040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 815 (or 800 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 891239040 is about 29853.6269153348. The cubic root of 891239040 is about 962.3463439426.

The spelling of 891239040 in words is "eight hundred ninety-one million, two hundred thirty-nine thousand, forty".