21059211 has 8 divisors (see below), whose sum is σ = 28102464. Its totient is φ = 14027720.

The previous prime is 21059197. The next prime is 21059219. The reversal of 21059211 is 11295012.

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

It is a cyclic number.

It is not a de Polignac number, because 21059211 - 2¹⁵ = 21026443 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21059219) 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 7 ways as a sum of consecutive naturals, for example, 2896 + ... + 7106.

It is an arithmetic number, because the mean of its divisors is an integer number (3512808).

Almost surely, 2^21059211 is an apocalyptic number.

21059211 is a deficient number, since it is larger than the sum of its proper divisors (7043253).

21059211 is a wasteful number, since it uses less digits than its factorization.

21059211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5881.

The product of its (nonzero) digits is 180, while the sum is 21.

The square root of 21059211 is about 4589.0315971891. The cubic root of 21059211 is about 276.1514737741.

The spelling of 21059211 in words is "twenty-one million, fifty-nine thousand, two hundred eleven".