21211293 has 4 divisors (see below), whose sum is σ = 28281728. Its totient is φ = 14140860.

The previous prime is 21211259. The next prime is 21211319. The reversal of 21211293 is 39211212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 21211293 - 2¹⁰ = 21210269 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21213293) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3535213 + ... + 3535218.

It is an arithmetic number, because the mean of its divisors is an integer number (7070432).

Almost surely, 2^21211293 is an apocalyptic number.

It is an amenable number.

21211293 is a deficient number, since it is larger than the sum of its proper divisors (7070435).

21211293 is an equidigital number, since it uses as much as digits as its factorization.

21211293 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7070434.

The product of its digits is 216, while the sum is 21.

The square root of 21211293 is about 4605.5719514518. The cubic root of 21211293 is about 276.8146352885.

The spelling of 21211293 in words is "twenty-one million, two hundred eleven thousand, two hundred ninety-three".