21845311 has 2 divisors, whose sum is σ = 21845312. Its totient is φ = 21845310.

The previous prime is 21845309. The next prime is 21845353. The reversal of 21845311 is 11354812.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21845311 - 2¹ = 21845309 is a prime.

It is a super-2 number, since 2×21845311² = 954435225373442, which contains 22 as substring.

Together with 21845309, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21845711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10922655 + 10922656.

It is an arithmetic number, because the mean of its divisors is an integer number (10922656).

Almost surely, 2^21845311 is an apocalyptic number.

21845311 is a deficient number, since it is larger than the sum of its proper divisors (1).

21845311 is an equidigital number, since it uses as much as digits as its factorization.

21845311 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 960, while the sum is 25.

The square root of 21845311 is about 4673.8967682224. The cubic root of 21845311 is about 279.5456534521.

The spelling of 21845311 in words is "twenty-one million, eight hundred forty-five thousand, three hundred eleven".