21056479 has 2 divisors, whose sum is σ = 21056480. Its totient is φ = 21056478.

The previous prime is 21056459. The next prime is 21056491. The reversal of 21056479 is 97465012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21056479 - 2⁵ = 21056447 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21056459) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10528239 + 10528240.

It is an arithmetic number, because the mean of its divisors is an integer number (10528240).

Almost surely, 2^21056479 is an apocalyptic number.

21056479 is a deficient number, since it is larger than the sum of its proper divisors (1).

21056479 is an equidigital number, since it uses as much as digits as its factorization.

21056479 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15120, while the sum is 34.

The square root of 21056479 is about 4588.7339212467. The cubic root of 21056479 is about 276.1395315974.

The spelling of 21056479 in words is "twenty-one million, fifty-six thousand, four hundred seventy-nine".