21833081 has 2 divisors, whose sum is σ = 21833082. Its totient is φ = 21833080.

The previous prime is 21833047. The next prime is 21833107. The reversal of 21833081 is 18033812.

It is an a-pointer prime, because the next prime (21833107) can be obtained adding 21833081 to its sum of digits (26).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21307456 + 525625 = 4616^2 + 725^2 .

It is a cyclic number.

It is not a de Polignac number, because 21833081 - 2⁶ = 21833017 is a prime.

It is a super-2 number, since 2×21833081² = 953366851905122, which contains 22 as substring.

It is equal to p_1379330 and since 21833081 and 1379330 have the same sum of digits, it is a Honaker prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21833081.

It is not a weakly prime, because it can be changed into another prime (21833041) 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, 10916540 + 10916541.

It is an arithmetic number, because the mean of its divisors is an integer number (10916541).

Almost surely, 2^21833081 is an apocalyptic number.

It is an amenable number.

21833081 is a deficient number, since it is larger than the sum of its proper divisors (1).

21833081 is an equidigital number, since it uses as much as digits as its factorization.

21833081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 21833081 is about 4672.5882549183. The cubic root of 21833081 is about 279.4934762511.

Adding to 21833081 its reverse (18033812), we get a palindrome (39866893).

The spelling of 21833081 in words is "twenty-one million, eight hundred thirty-three thousand, eighty-one".