21419173 has 2 divisors, whose sum is σ = 21419174. Its totient is φ = 21419172.

The previous prime is 21419143. The next prime is 21419207. The reversal of 21419173 is 37191412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20493729 + 925444 = 4527^2 + 962^2 .

It is a cyclic number.

It is not a de Polignac number, because 21419173 - 2¹³ = 21410981 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21419143) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10709586 + 10709587.

It is an arithmetic number, because the mean of its divisors is an integer number (10709587).

Almost surely, 2^21419173 is an apocalyptic number.

It is an amenable number.

21419173 is a deficient number, since it is larger than the sum of its proper divisors (1).

21419173 is an equidigital number, since it uses as much as digits as its factorization.

21419173 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1512, while the sum is 28.

The square root of 21419173 is about 4628.0852412202. The cubic root of 21419173 is about 277.7159988063.

The spelling of 21419173 in words is "twenty-one million, four hundred nineteen thousand, one hundred seventy-three".