891772096720 has 160 divisors (see below), whose sum is σ = 2256161408928. Its totient is φ = 326435733504.

The previous prime is 891772096673. The next prime is 891772096741. The reversal of 891772096720 is 27690277198.

It can be written as a sum of positive squares in 16 ways, for example, as 77749514896 + 814022581824 = 278836^2 + 902232^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 89413654 + ... + 89423626.

Almost surely, 2^891772096720 is an apocalyptic number.

891772096720 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 891772096720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1128080704464).

891772096720 is an abundant number, since it is smaller than the sum of its proper divisors (1364389312208).

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

891772096720 is a wasteful number, since it uses less digits than its factorization.

891772096720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11817 (or 11811 counting only the distinct ones).

The product of its (nonzero) digits is 5334336, while the sum is 58.

The spelling of 891772096720 in words is "eight hundred ninety-one billion, seven hundred seventy-two million, ninety-six thousand, seven hundred twenty".