21270293 has 4 divisors (see below), whose sum is σ = 23203968. Its totient is φ = 19336620.

The previous prime is 21270269. The next prime is 21270299. The reversal of 21270293 is 39207212.

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 a cyclic number.

It is not a de Polignac number, because 21270293 - 2⁸ = 21270037 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 (21270299) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 966821 + ... + 966842.

It is an arithmetic number, because the mean of its divisors is an integer number (5800992).

Almost surely, 2^21270293 is an apocalyptic number.

It is an amenable number.

21270293 is a deficient number, since it is larger than the sum of its proper divisors (1933675).

21270293 is a wasteful number, since it uses less digits than its factorization.

21270293 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1933674.

The product of its (nonzero) digits is 1512, while the sum is 26.

The square root of 21270293 is about 4611.9727882979. The cubic root of 21270293 is about 277.0710544216.

The spelling of 21270293 in words is "twenty-one million, two hundred seventy thousand, two hundred ninety-three".