21479424 has 120 divisors (see below), whose sum is σ = 62912640. Its totient is φ = 6488064.

The previous prime is 21479407. The next prime is 21479429. The reversal of 21479424 is 42497412.

It is a super-2 number, since 2×21479424² = 922731310743552, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21479429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 933877 + ... + 933899.

It is an arithmetic number, because the mean of its divisors is an integer number (524272).

Almost surely, 2^21479424 is an apocalyptic number.

21479424 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21479424, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31456320).

21479424 is an abundant number, since it is smaller than the sum of its proper divisors (41433216).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21479424 is an equidigital number, since it uses as much as digits as its factorization.

21479424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73 (or 47 counting only the distinct ones).

The product of its digits is 16128, while the sum is 33.

The square root of 21479424 is about 4634.5899494993. The cubic root of 21479424 is about 277.9761551586.

The spelling of 21479424 in words is "twenty-one million, four hundred seventy-nine thousand, four hundred twenty-four".