108111821 has 2 divisors, whose sum is σ = 108111822. Its totient is φ = 108111820.

The previous prime is 108111763. The next prime is 108111833. The reversal of 108111821 is 128111801.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 58690921 + 49420900 = 7661^2 + 7030^2 .

It is a cyclic number.

It is not a de Polignac number, because 108111821 - 2¹⁰ = 108110797 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (108111841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 54055910 + 54055911.

It is an arithmetic number, because the mean of its divisors is an integer number (54055911).

Almost surely, 2^108111821 is an apocalyptic number.

It is an amenable number.

108111821 is a deficient number, since it is larger than the sum of its proper divisors (1).

108111821 is an equidigital number, since it uses as much as digits as its factorization.

108111821 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 23.

The square root of 108111821 is about 10397.6834439215. The cubic root of 108111821 is about 476.3846151707.

The spelling of 108111821 in words is "one hundred eight million, one hundred eleven thousand, eight hundred twenty-one".