21899783 has 2 divisors, whose sum is σ = 21899784. Its totient is φ = 21899782.

The previous prime is 21899777. The next prime is 21899803. The reversal of 21899783 is 38799812.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21899783 - 2⁶ = 21899719 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21899743) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10949891 + 10949892.

It is an arithmetic number, because the mean of its divisors is an integer number (10949892).

Almost surely, 2^21899783 is an apocalyptic number.

21899783 is a deficient number, since it is larger than the sum of its proper divisors (1).

21899783 is an equidigital number, since it uses as much as digits as its factorization.

21899783 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 217728, while the sum is 47.

The square root of 21899783 is about 4679.7203976306. The cubic root of 21899783 is about 279.7778126808. Note that the first 3 decimals are identical.

It can be divided in two parts, 218 and 99783, that added together give a palindrome (100001).

The spelling of 21899783 in words is "twenty-one million, eight hundred ninety-nine thousand, seven hundred eighty-three".