22085821 has 2 divisors, whose sum is σ = 22085822. Its totient is φ = 22085820.

The previous prime is 22085807. The next prime is 22085827. The reversal of 22085821 is 12858022.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21576025 + 509796 = 4645^2 + 714^2 .

It is a cyclic number.

It is not a de Polignac number, because 22085821 - 2⁹ = 22085309 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 22085821.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22085827) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11042910 + 11042911.

It is an arithmetic number, because the mean of its divisors is an integer number (11042911).

Almost surely, 2^22085821 is an apocalyptic number.

It is an amenable number.

22085821 is a deficient number, since it is larger than the sum of its proper divisors (1).

22085821 is an equidigital number, since it uses as much as digits as its factorization.

22085821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2560, while the sum is 28.

The square root of 22085821 is about 4699.5554045037. Note that the first 3 decimals coincide. The cubic root of 22085821 is about 280.5678145819.

The spelling of 22085821 in words is "twenty-two million, eighty-five thousand, eight hundred twenty-one".