21735419 has 2 divisors, whose sum is σ = 21735420. Its totient is φ = 21735418.

The previous prime is 21735409. The next prime is 21735421. The reversal of 21735419 is 91453712.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21735419 - 2²⁰ = 20686843 is a prime.

It is a super-2 number, since 2×21735419² = 944856878211122, which contains 22 as substring.

Together with 21735421, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21735409) 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, 10867709 + 10867710.

It is an arithmetic number, because the mean of its divisors is an integer number (10867710).

Almost surely, 2^21735419 is an apocalyptic number.

21735419 is a deficient number, since it is larger than the sum of its proper divisors (1).

21735419 is an equidigital number, since it uses as much as digits as its factorization.

21735419 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7560, while the sum is 32.

The square root of 21735419 is about 4662.1260171729. The cubic root of 21735419 is about 279.0761173422.

The spelling of 21735419 in words is "twenty-one million, seven hundred thirty-five thousand, four hundred nineteen".