10811821 has 2 divisors, whose sum is σ = 10811822. Its totient is φ = 10811820.

The previous prime is 10811803. The next prime is 10811831. The reversal of 10811821 is 12811801.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8820900 + 1990921 = 2970^2 + 1411^2 .

It is a cyclic number.

It is not a de Polignac number, because 10811821 - 2⁵ = 10811789 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 10811792 and 10811801.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (10811831) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5405910 + 5405911.

It is an arithmetic number, because the mean of its divisors is an integer number (5405911).

Almost surely, 2^10811821 is an apocalyptic number.

It is an amenable number.

10811821 is a deficient number, since it is larger than the sum of its proper divisors (1).

10811821 is an equidigital number, since it uses as much as digits as its factorization.

10811821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 128, while the sum is 22.

The square root of 10811821 is about 3288.1333610424. The cubic root of 10811821 is about 221.1225066913.

The spelling of 10811821 in words is "ten million, eight hundred eleven thousand, eight hundred twenty-one".