105567821 has 2 divisors, whose sum is σ = 105567822. Its totient is φ = 105567820.

The previous prime is 105567809. The next prime is 105567829. The reversal of 105567821 is 128765501.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 101808100 + 3759721 = 10090^2 + 1939^2 .

It is an emirp because it is prime and its reverse (128765501) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 105567821 - 2¹⁴ = 105551437 is a prime.

It is a super-2 number, since 2×105567821² = 22289129661376082, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen 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 (105567829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 52783910 + 52783911.

It is an arithmetic number, because the mean of its divisors is an integer number (52783911).

Almost surely, 2^105567821 is an apocalyptic number.

It is an amenable number.

105567821 is a deficient number, since it is larger than the sum of its proper divisors (1).

105567821 is an equidigital number, since it uses as much as digits as its factorization.

105567821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16800, while the sum is 35.

The square root of 105567821 is about 10274.6202362910. The cubic root of 105567821 is about 472.6182841703.

The spelling of 105567821 in words is "one hundred five million, five hundred sixty-seven thousand, eight hundred twenty-one".