891181921352 has 36 divisors (see below), whose sum is σ = 1700068111305. Its totient is φ = 437961138496.

The previous prime is 891181921351. The next prime is 891181921361. The reversal of 891181921352 is 253129181198.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in 2 ways, for example, as 712427154916 + 178754766436 = 844054^2 + 422794^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=667526.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 891181921352.

It is not an unprimeable number, because it can be changed into a prime (891181921351) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 157533308 + ... + 157538964.

Almost surely, 2^891181921352 is an apocalyptic number.

It is an amenable number.

891181921352 is a deficient number, since it is larger than the sum of its proper divisors (808886189953).

891181921352 is an frugal number, since it uses more digits than its factorization.

891181921352 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11438 (or 5718 counting only the distinct ones).

The product of its digits is 311040, while the sum is 50.

Multiplying 891181921352 by its sum of digits (50), we get a square (44559096067600 = 6675260²).

The spelling of 891181921352 in words is "eight hundred ninety-one billion, one hundred eighty-one million, nine hundred twenty-one thousand, three hundred fifty-two".