891931225680 has 640 divisors, whose sum is σ = 3532916736000. Its totient is φ = 204554004480.

The previous prime is 891931225637. The next prime is 891931225733. The reversal of 891931225680 is 86522139198.

It is a super-2 number, since 2×891931225680² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 619826401 + ... + 619827839.

It is an arithmetic number, because the mean of its divisors is an integer number (5520182400).

Almost surely, 2^891931225680 is an apocalyptic number.

891931225680 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 891931225680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1766458368000).

891931225680 is an abundant number, since it is smaller than the sum of its proper divisors (2640985510320).

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

891931225680 is a wasteful number, since it uses less digits than its factorization.

891931225680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2864 (or 2852 counting only the distinct ones).

The product of its (nonzero) digits is 1866240, while the sum is 54.

The spelling of 891931225680 in words is "eight hundred ninety-one billion, nine hundred thirty-one million, two hundred twenty-five thousand, six hundred eighty".