85866421 has 2 divisors, whose sum is σ = 85866422. Its totient is φ = 85866420.

The previous prime is 85866401. The next prime is 85866481. The reversal of 85866421 is 12466858.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 83010321 + 2856100 = 9111^2 + 1690^2 .

It is a cyclic number.

It is not a de Polignac number, because 85866421 - 2⁷ = 85866293 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (85866401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42933210 + 42933211.

It is an arithmetic number, because the mean of its divisors is an integer number (42933211).

Almost surely, 2^85866421 is an apocalyptic number.

It is an amenable number.

85866421 is a deficient number, since it is larger than the sum of its proper divisors (1).

85866421 is an equidigital number, since it uses as much as digits as its factorization.

85866421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 92160, while the sum is 40.

The square root of 85866421 is about 9266.4135996620. The cubic root of 85866421 is about 441.1718435673.

The spelling of 85866421 in words is "eighty-five million, eight hundred sixty-six thousand, four hundred twenty-one".