21096859 has 16 divisors (see below), whose sum is σ = 25600000. Its totient is φ = 16982784.

The previous prime is 21096839. The next prime is 21096877. The reversal of 21096859 is 95869012.

It is not a de Polignac number, because 21096859 - 2⁹ = 21096347 is a prime.

It is a super-3 number, since 3×21096859³ (a number of 23 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21096839) 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 15 ways as a sum of consecutive naturals, for example, 16267 + ... + 17515.

It is an arithmetic number, because the mean of its divisors is an integer number (1600000).

Almost surely, 2^21096859 is an apocalyptic number.

21096859 is a deficient number, since it is larger than the sum of its proper divisors (4503141).

21096859 is a wasteful number, since it uses less digits than its factorization.

21096859 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1402.

The product of its (nonzero) digits is 38880, while the sum is 40.

The square root of 21096859 is about 4593.1317202972. The cubic root of 21096859 is about 276.3159364321.

The spelling of 21096859 in words is "twenty-one million, ninety-six thousand, eight hundred fifty-nine".