21179419 has 4 divisors (see below), whose sum is σ = 21417480. Its totient is φ = 20941360.

The previous prime is 21179413. The next prime is 21179423. The reversal of 21179419 is 91497112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21179419 is a prime.

It is a super-2 number, since 2×21179419² = 897135578355122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21179413) 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 in 3 ways as a sum of consecutive naturals, for example, 118897 + ... + 119074.

It is an arithmetic number, because the mean of its divisors is an integer number (5354370).

Almost surely, 2^21179419 is an apocalyptic number.

21179419 is a deficient number, since it is larger than the sum of its proper divisors (238061).

21179419 is an equidigital number, since it uses as much as digits as its factorization.

21179419 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 238060.

The product of its digits is 4536, while the sum is 34.

The square root of 21179419 is about 4602.1102768187. The cubic root of 21179419 is about 276.6759102410.

The spelling of 21179419 in words is "twenty-one million, one hundred seventy-nine thousand, four hundred nineteen".