21011479 has 4 divisors (see below), whose sum is σ = 21407976. Its totient is φ = 20614984.

The previous prime is 21011453. The next prime is 21011503. The reversal of 21011479 is 97411012.

21011479 is nontrivially palindromic in base 12.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21011479 - 2⁵ = 21011447 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 (21011579) 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, 198169 + ... + 198274.

It is an arithmetic number, because the mean of its divisors is an integer number (5351994).

Almost surely, 2^21011479 is an apocalyptic number.

21011479 is a deficient number, since it is larger than the sum of its proper divisors (396497).

21011479 is an equidigital number, since it uses as much as digits as its factorization.

21011479 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 396496.

The product of its (nonzero) digits is 504, while the sum is 25.

The square root of 21011479 is about 4583.8279854288. The cubic root of 21011479 is about 275.9426778317.

The spelling of 21011479 in words is "twenty-one million, eleven thousand, four hundred seventy-nine".