891397134485280 has 672 divisors, whose sum is σ = 3341989551176640. Its totient is φ = 223950793144320.

The previous prime is 891397134485251. The next prime is 891397134485287. The reversal of 891397134485280 is 82584431793198.

891397134485280 is a `hidden beast` number, since 8 + 9 + 1 + 3 + 9 + 7 + 134 + 485 + 2 + 8 + 0 = 666.

It is a super-2 number, since 2×891397134485280² (a number of 31 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a junction number, because it is equal to n+sod(n) for n = 891397134485199 and 891397134485208.

It is not an unprimeable number, because it can be changed into a prime (891397134485287) by changing a digit.

It is a polite number, since it can be written in 111 ways as a sum of consecutive naturals, for example, 400013839 + ... + 402236081.

It is an arithmetic number, because the mean of its divisors is an integer number (4973198736870).

Almost surely, 2^{891397134485280} is an apocalyptic number.

891397134485280 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 891397134485280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1670994775588320).

891397134485280 is an abundant number, since it is smaller than the sum of its proper divisors (2450592416691360).

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

891397134485280 is a wasteful number, since it uses less digits than its factorization.

891397134485280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2222476 (or 2222453 counting only the distinct ones).

The product of its (nonzero) digits is 418037760, while the sum is 72.

The spelling of 891397134485280 in words is "eight hundred ninety-one trillion, three hundred ninety-seven billion, one hundred thirty-four million, four hundred eighty-five thousand, two hundred eighty".