21424619 has 2 divisors, whose sum is σ = 21424620. Its totient is φ = 21424618.

The previous prime is 21424589. The next prime is 21424631. The reversal of 21424619 is 91642412.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21424619 - 2¹⁶ = 21359083 is a prime.

It is a super-2 number, since 2×21424619² = 918028598590322, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21424591 and 21424600.

It is not a weakly prime, because it can be changed into another prime (21424679) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10712309 + 10712310.

It is an arithmetic number, because the mean of its divisors is an integer number (10712310).

Almost surely, 2^21424619 is an apocalyptic number.

21424619 is a deficient number, since it is larger than the sum of its proper divisors (1).

21424619 is an equidigital number, since it uses as much as digits as its factorization.

21424619 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3456, while the sum is 29.

The square root of 21424619 is about 4628.6735680970. The cubic root of 21424619 is about 277.7395340001.

The spelling of 21424619 in words is "twenty-one million, four hundred twenty-four thousand, six hundred nineteen".