21056029 has 2 divisors, whose sum is σ = 21056030. Its totient is φ = 21056028.

The previous prime is 21056027. The next prime is 21056033. The reversal of 21056029 is 92065012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16016004 + 5040025 = 4002^2 + 2245^2 .

It is a cyclic number.

It is not a de Polignac number, because 21056029 - 2¹ = 21056027 is a prime.

Together with 21056027, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 21055994 and 21056012.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21056027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10528014 + 10528015.

It is an arithmetic number, because the mean of its divisors is an integer number (10528015).

Almost surely, 2^21056029 is an apocalyptic number.

It is an amenable number.

21056029 is a deficient number, since it is larger than the sum of its proper divisors (1).

21056029 is an equidigital number, since it uses as much as digits as its factorization.

21056029 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1080, while the sum is 25.

The square root of 21056029 is about 4588.6848878519. The cubic root of 21056029 is about 276.1375644487.

The spelling of 21056029 in words is "twenty-one million, fifty-six thousand, twenty-nine".