21839619 has 8 divisors (see below), whose sum is σ = 29228032. Its totient is φ = 14505480.

The previous prime is 21839599. The next prime is 21839633. The reversal of 21839619 is 91693812.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21839619 - 2⁷ = 21839491 is a prime.

It is a super-2 number, since 2×21839619² = 953937916130322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21839659) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12619 + ... + 14244.

It is an arithmetic number, because the mean of its divisors is an integer number (3653504).

Almost surely, 2^21839619 is an apocalyptic number.

21839619 is a deficient number, since it is larger than the sum of its proper divisors (7388413).

21839619 is a wasteful number, since it uses less digits than its factorization.

21839619 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27137.

The product of its digits is 23328, while the sum is 39.

The square root of 21839619 is about 4673.2878148045. The cubic root of 21839619 is about 279.5213719319.

The spelling of 21839619 in words is "twenty-one million, eight hundred thirty-nine thousand, six hundred nineteen".