21059519 has 8 divisors (see below), whose sum is σ = 23064720. Its totient is φ = 19109376.

The previous prime is 21059477. The next prime is 21059537. The reversal of 21059519 is 91595012.

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

It is not a de Polignac number, because 21059519 - 2⁸ = 21059263 is a prime.

It is a super-2 number, since 2×21059519² = 887006681022722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21059569) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12962 + ... + 14495.

It is an arithmetic number, because the mean of its divisors is an integer number (2883090).

Almost surely, 2^21059519 is an apocalyptic number.

21059519 is a deficient number, since it is larger than the sum of its proper divisors (2005201).

21059519 is a wasteful number, since it uses less digits than its factorization.

21059519 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27529.

The product of its (nonzero) digits is 4050, while the sum is 32.

The square root of 21059519 is about 4589.0651553448. The cubic root of 21059519 is about 276.1528200455.

The spelling of 21059519 in words is "twenty-one million, fifty-nine thousand, five hundred nineteen".