21994183 has 2 divisors, whose sum is σ = 21994184. Its totient is φ = 21994182.

The previous prime is 21994177. The next prime is 21994211. The reversal of 21994183 is 38149912.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21994183 is a prime.

It is equal to p_1388926 and since 21994183 and 1388926 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21994123) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10997091 + 10997092.

It is an arithmetic number, because the mean of its divisors is an integer number (10997092).

Almost surely, 2^21994183 is an apocalyptic number.

21994183 is a deficient number, since it is larger than the sum of its proper divisors (1).

21994183 is an equidigital number, since it uses as much as digits as its factorization.

21994183 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15552, while the sum is 37.

The square root of 21994183 is about 4689.7956245448. The cubic root of 21994183 is about 280.1792347329.

The spelling of 21994183 in words is "twenty-one million, nine hundred ninety-four thousand, one hundred eighty-three".