21211093 has 8 divisors (see below), whose sum is σ = 21997080. Its totient is φ = 20428800.

The previous prime is 21211079. The next prime is 21211109. The reversal of 21211093 is 39011212.

It can be written as a sum of positive squares in 4 ways, for example, as 5026564 + 16184529 = 2242^2 + 4023^2 .

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 21211093 - 2¹³ = 21202901 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21211093.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21211013) 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, 16821 + ... + 18037.

It is an arithmetic number, because the mean of its divisors is an integer number (2749635).

Almost surely, 2^21211093 is an apocalyptic number.

It is an amenable number.

21211093 is a deficient number, since it is larger than the sum of its proper divisors (785987).

21211093 is a wasteful number, since it uses less digits than its factorization.

21211093 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1847.

The product of its (nonzero) digits is 108, while the sum is 19.

The square root of 21211093 is about 4605.5502385708. The cubic root of 21211093 is about 276.8137652629.

The spelling of 21211093 in words is "twenty-one million, two hundred eleven thousand, ninety-three".