891647280 has 240 divisors, whose sum is σ = 3207544704. Its totient is φ = 221184000.

The previous prime is 891647261. The next prime is 891647287. The reversal of 891647280 is 82746198.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (891647287) 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, 1186905 + ... + 1187655.

Almost surely, 2^891647280 is an apocalyptic number.

891647280 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 891647280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1603772352).

891647280 is an abundant number, since it is smaller than the sum of its proper divisors (2315897424).

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

891647280 is a wasteful number, since it uses less digits than its factorization.

891647280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 884 (or 875 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 45.

The square root of 891647280 is about 29860.4634927189. The cubic root of 891647280 is about 962.4932586248.

The spelling of 891647280 in words is "eight hundred ninety-one million, six hundred forty-seven thousand, two hundred eighty".