10161821 has 2 divisors, whose sum is σ = 10161822. Its totient is φ = 10161820.

The previous prime is 10161797. The next prime is 10161841. The reversal of 10161821 is 12816101.

It is an a-pointer prime, because the next prime (10161841) can be obtained adding 10161821 to its sum of digits (20).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9369721 + 792100 = 3061^2 + 890^2 .

It is a cyclic number.

It is not a de Polignac number, because 10161821 - 2⁶ = 10161757 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 10161793 and 10161802.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (10161841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5080910 + 5080911.

It is an arithmetic number, because the mean of its divisors is an integer number (5080911).

Almost surely, 2^10161821 is an apocalyptic number.

It is an amenable number.

10161821 is a deficient number, since it is larger than the sum of its proper divisors (1).

10161821 is an equidigital number, since it uses as much as digits as its factorization.

10161821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96, while the sum is 20.

The square root of 10161821 is about 3187.7611265589. The cubic root of 10161821 is about 216.5993655533.

Adding to 10161821 its reverse (12816101), we get a palindrome (22977922).

The spelling of 10161821 in words is "ten million, one hundred sixty-one thousand, eight hundred twenty-one".