891478820329 has 2 divisors, whose sum is σ = 891478820330. Its totient is φ = 891478820328.

The previous prime is 891478820249. The next prime is 891478820339. The reversal of 891478820329 is 923028874198.

891478820329 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 859106534400 + 32372285929 = 926880^2 + 179923^2 .

It is a cyclic number.

It is not a de Polignac number, because 891478820329 - 2¹¹ = 891478818281 is a prime.

It is not a weakly prime, because it can be changed into another prime (891478820339) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 445739410164 + 445739410165.

It is an arithmetic number, because the mean of its divisors is an integer number (445739410165).

Almost surely, 2^891478820329 is an apocalyptic number.

It is an amenable number.

891478820329 is a deficient number, since it is larger than the sum of its proper divisors (1).

891478820329 is an equidigital number, since it uses as much as digits as its factorization.

891478820329 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13934592, while the sum is 61.

The spelling of 891478820329 in words is "eight hundred ninety-one billion, four hundred seventy-eight million, eight hundred twenty thousand, three hundred twenty-nine".