21429719 has 2 divisors, whose sum is σ = 21429720. Its totient is φ = 21429718.

The previous prime is 21429703. The next prime is 21429731. The reversal of 21429719 is 91792412.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21429719 - 2⁴ = 21429703 is a prime.

It is a super-2 number, since 2×21429719² = 918465712837922, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21429799) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10714859 + 10714860.

It is an arithmetic number, because the mean of its divisors is an integer number (10714860).

Almost surely, 2^21429719 is an apocalyptic number.

21429719 is a deficient number, since it is larger than the sum of its proper divisors (1).

21429719 is an equidigital number, since it uses as much as digits as its factorization.

21429719 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9072, while the sum is 35.

The square root of 21429719 is about 4629.2244490843. The cubic root of 21429719 is about 277.7615703195.

The spelling of 21429719 in words is "twenty-one million, four hundred twenty-nine thousand, seven hundred nineteen".