21022007 has 2 divisors, whose sum is σ = 21022008. Its totient is φ = 21022006.

The previous prime is 21021997. The next prime is 21022009. The reversal of 21022007 is 70022012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21022007 - 2¹⁴ = 21005623 is a prime.

Together with 21022009, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 21021982 and 21022000.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21022009) 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, 10511003 + 10511004.

It is an arithmetic number, because the mean of its divisors is an integer number (10511004).

Almost surely, 2^21022007 is an apocalyptic number.

21022007 is a deficient number, since it is larger than the sum of its proper divisors (1).

21022007 is an equidigital number, since it uses as much as digits as its factorization.

21022007 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 56, while the sum is 14.

The square root of 21022007 is about 4584.9762267650. The cubic root of 21022007 is about 275.9887580312.

Adding to 21022007 its reverse (70022012), we get a palindrome (91044019).

The spelling of 21022007 in words is "twenty-one million, twenty-two thousand, seven".