21860429 has 2 divisors, whose sum is σ = 21860430. Its totient is φ = 21860428.

The previous prime is 21860417. The next prime is 21860441. The reversal of 21860429 is 92406812.

It is a balanced prime because it is at equal distance from previous prime (21860417) and next prime (21860441).

It can be written as a sum of positive squares in only one way, i.e., 21808900 + 51529 = 4670^2 + 227^2 .

It is a cyclic number.

It is not a de Polignac number, because 21860429 - 2²⁰ = 20811853 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21860395 and 21860404.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21860459) 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, 10930214 + 10930215.

It is an arithmetic number, because the mean of its divisors is an integer number (10930215).

Almost surely, 2^21860429 is an apocalyptic number.

It is an amenable number.

21860429 is a deficient number, since it is larger than the sum of its proper divisors (1).

21860429 is an equidigital number, since it uses as much as digits as its factorization.

21860429 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6912, while the sum is 32.

The square root of 21860429 is about 4675.5137685606. The cubic root of 21860429 is about 279.6101249026.

The spelling of 21860429 in words is "twenty-one million, eight hundred sixty thousand, four hundred twenty-nine".