21430271 has 8 divisors (see below), whose sum is σ = 22604400. Its totient is φ = 20260800.

The previous prime is 21430259. The next prime is 21430291. The reversal of 21430271 is 17203412.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21430271 is a prime.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21430291) 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, 12515 + ... + 14123.

It is an arithmetic number, because the mean of its divisors is an integer number (2825550).

Almost surely, 2^21430271 is an apocalyptic number.

21430271 is a deficient number, since it is larger than the sum of its proper divisors (1174129).

21430271 is a wasteful number, since it uses less digits than its factorization.

21430271 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2329.

The product of its (nonzero) digits is 336, while the sum is 20.

The square root of 21430271 is about 4629.2840699184. The cubic root of 21430271 is about 277.7639552174.

Adding to 21430271 its reverse (17203412), we get a palindrome (38633683).

The spelling of 21430271 in words is "twenty-one million, four hundred thirty thousand, two hundred seventy-one".