916821889 has 2 divisors, whose sum is σ = 916821890. Its totient is φ = 916821888.

The previous prime is 916821823. The next prime is 916821943. The reversal of 916821889 is 988128619.

916821889 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., 561310864 + 355511025 = 23692^2 + 18855^2 .

It is a cyclic number.

It is not a de Polignac number, because 916821889 - 2⁷ = 916821761 is a prime.

It is a super-2 number, since 2×916821889² = 1681124752299056642, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (916021889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 458410944 + 458410945.

It is an arithmetic number, because the mean of its divisors is an integer number (458410945).

Almost surely, 2^916821889 is an apocalyptic number.

It is an amenable number.

916821889 is a deficient number, since it is larger than the sum of its proper divisors (1).

916821889 is an equidigital number, since it uses as much as digits as its factorization.

916821889 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 497664, while the sum is 52.

The square root of 916821889 is about 30279.0668449343. The cubic root of 916821889 is about 971.4676083413.

The spelling of 916821889 in words is "nine hundred sixteen million, eight hundred twenty-one thousand, eight hundred eighty-nine".