866220881 has 2 divisors, whose sum is σ = 866220882. Its totient is φ = 866220880.

The previous prime is 866220869. The next prime is 866220889. The reversal of 866220881 is 188022668.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 754051600 + 112169281 = 27460^2 + 10591^2 .

It is a cyclic number.

It is not a de Polignac number, because 866220881 - 2¹⁰ = 866219857 is a prime.

It is a super-2 number, since 2×866220881² = 1500677229360832322, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (866220889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 433110440 + 433110441.

It is an arithmetic number, because the mean of its divisors is an integer number (433110441).

Almost surely, 2^866220881 is an apocalyptic number.

It is an amenable number.

866220881 is a deficient number, since it is larger than the sum of its proper divisors (1).

866220881 is an equidigital number, since it uses as much as digits as its factorization.

866220881 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 73728, while the sum is 41.

The square root of 866220881 is about 29431.6306208134. The cubic root of 866220881 is about 953.2560044400.

The spelling of 866220881 in words is "eight hundred sixty-six million, two hundred twenty thousand, eight hundred eighty-one".