21286479 has 8 divisors (see below), whose sum is σ = 29875840. Its totient is φ = 13444056.

The previous prime is 21286451. The next prime is 21286483. The reversal of 21286479 is 97468212.

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

It is not a de Polignac number, because 21286479 - 2⁷ = 21286351 is a prime.

It is a super-2 number, since 2×21286479² = 906228376434882, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21286409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 186667 + ... + 186780.

It is an arithmetic number, because the mean of its divisors is an integer number (3734480).

Almost surely, 2^21286479 is an apocalyptic number.

21286479 is a deficient number, since it is larger than the sum of its proper divisors (8589361).

21286479 is a wasteful number, since it uses less digits than its factorization.

21286479 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 373469.

The product of its digits is 48384, while the sum is 39.

The square root of 21286479 is about 4613.7272351105. The cubic root of 21286479 is about 277.1413172839.

The spelling of 21286479 in words is "twenty-one million, two hundred eighty-six thousand, four hundred seventy-nine".