21450029 has 2 divisors, whose sum is σ = 21450030. Its totient is φ = 21450028.

The previous prime is 21450019. The next prime is 21450061. The reversal of 21450029 is 92005412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16728100 + 4721929 = 4090^2 + 2173^2 .

It is a cyclic number.

It is not a de Polignac number, because 21450029 - 2¹² = 21445933 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is equal to p_1356602 and since 21450029 and 1356602 have the same sum of digits, it is a Honaker prime.

It is a junction number, because it is equal to n+sod(n) for n = 21449986 and 21450013.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21450019) 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, 10725014 + 10725015.

It is an arithmetic number, because the mean of its divisors is an integer number (10725015).

Almost surely, 2^21450029 is an apocalyptic number.

It is an amenable number.

21450029 is a deficient number, since it is larger than the sum of its proper divisors (1).

21450029 is an equidigital number, since it uses as much as digits as its factorization.

21450029 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 21450029 is about 4631.4176015557. The cubic root of 21450029 is about 277.8492920522.

The spelling of 21450029 in words is "twenty-one million, four hundred fifty thousand, twenty-nine".