21102293 has 16 divisors (see below), whose sum is σ = 23738880. Its totient is φ = 18661104.

The previous prime is 21102281. The next prime is 21102307. The reversal of 21102293 is 39220112.

It is a cyclic number.

It is not a de Polignac number, because 21102293 - 2²⁰ = 20053717 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21102493) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18230 + ... + 19352.

It is an arithmetic number, because the mean of its divisors is an integer number (1483680).

Almost surely, 2^21102293 is an apocalyptic number.

21102293 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

21102293 is a deficient number, since it is larger than the sum of its proper divisors (2636587).

21102293 is a wasteful number, since it uses less digits than its factorization.

21102293 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1208.

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 21102293 is about 4593.7232176090. The cubic root of 21102293 is about 276.3396583189.

It can be divided in two parts, 21102 and 293, that multiplied together give a triangular number (6182886 = T₃₅₁₆).

The spelling of 21102293 in words is "twenty-one million, one hundred two thousand, two hundred ninety-three".