21208093 has 8 divisors (see below), whose sum is σ = 22269888. Its totient is φ = 20157984.

The previous prime is 21208091. The next prime is 21208097. The reversal of 21208093 is 39080212.

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 21208093 - 2¹ = 21208091 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21208091) 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, 921 + ... + 6577.

It is an arithmetic number, because the mean of its divisors is an integer number (2783736).

Almost surely, 2^21208093 is an apocalyptic number.

21208093 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

21208093 is a deficient number, since it is larger than the sum of its proper divisors (1061795).

21208093 is a wasteful number, since it uses less digits than its factorization.

21208093 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5843.

The product of its (nonzero) digits is 864, while the sum is 25.

The square root of 21208093 is about 4605.2245330711. The cubic root of 21208093 is about 276.8007142232.

The spelling of 21208093 in words is "twenty-one million, two hundred eight thousand, ninety-three".