21479311 has 16 divisors (see below), whose sum is σ = 25612288. Its totient is φ = 17643960.

The previous prime is 21479303. The next prime is 21479333. The reversal of 21479311 is 11397412.

It is not a de Polignac number, because 21479311 - 2³ = 21479303 is a prime.

It is a super-2 number, since 2×21479311² = 922721602069442, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21479311.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21479371) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 208486 + ... + 208588.

It is an arithmetic number, because the mean of its divisors is an integer number (1600768).

Almost surely, 2^21479311 is an apocalyptic number.

21479311 is a deficient number, since it is larger than the sum of its proper divisors (4132977).

21479311 is an frugal number, since it uses more digits than its factorization.

21479311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 203 (or 141 counting only the distinct ones).

The product of its digits is 1512, while the sum is 28.

The square root of 21479311 is about 4634.5777585450. The cubic root of 21479311 is about 277.9756676942.

The spelling of 21479311 in words is "twenty-one million, four hundred seventy-nine thousand, three hundred eleven".